Stems

Get back on the road with a genuine replacement stem. Original equipment replacement stem for your Madone SLR. PRODUCT DETAILS - High fit stem is 7-degrees of drop - Not compatible with other bikes - For installation instructions, please see your Madone Assembly Manual

Zipp's SL Speed stem represents the essence of carbon componentry. It's stiff, secure and light weight with a sleek design that compliments any bike. It's a perfect addition to a mountain climber's favorite feather-light road bike, but it's tough enough to tackle gravel and cyclocross. Designed using SRAM Exogram technology, found in SRAM RED cranks, the new SL Speed Stem weighs just 123g (100mm) while exceeding our stiffness-to-weight standards. The SL Speed is available in six sizes ranging from 70 to 120mm to meet any rider's fit needs. Includes stiff aluminum faceplate and titanium hardware Torx T25 heads for precise torque readings and ease of adjustment. - Updated distinctive Zipp cosmetics - Designed using SRAM Exogram technology - New SL Speed Stem weighs just 123g (100mm) - ±6° carbon stem - Secure with four bolt faceplace using Torx T25 bolt heads - Matte Black finish - Lifetime warranty - Zipp Quickview integrated mount available separately

The SL Sprint Stem is an ideal balance of stiffness and lightweight. The stem weighs in at just 1.8g per newton meter of stiffness using SRAM's Exogram technology. Designed with feedback from top pros to meet the unrelenting demands of Grand Tour sprinters. Zipp also tapped into expertise gained from its pioneering carbon stems and exhaustively researched the marketplace to create the SL Sprint Stem. The SL Sprint comes with its own stem cap that's designed to be aerodynamically efficient by blending into the stem body. Available in six sizes, ranging from 90 to 140mm, to meet any rider's fit needs. - Updated distinctive Zipp cosmetics - Carbon Exogram construction delivers the stiffest stem on the market gram for gram. - Secure with four bolt faceplace using Torx T25 bolt heads - Matte Black finish - Lifetime warranty - Zipp Quickview integrated computer mount available separately

- Full UD carbon construction stem - 4 bolt aluminum faceplate for added rigidity - Stainless steel hardware - Reversible +/-7° angle - 40mm stack height - 125g weight in 100mm length - ISO-Road safety certified

eeSilk Stem is a fatigue-reducing compliance stem that noticeably reduces vibrations on variable surfaces. With up to 20mm of tunable compliance, an easy single bolt external elastomer change and a soft/firm compliance switch – the eeSilk Stem makes any road, no matter the terrain, smoother. - Weight: 225g - 235g - Angle: -6° (only) - Stack Height: 49mm - Stem Clamp: 31.8mm

FSA's K-Force OS-99 CSI is 3-D forged and CNC machined from AL2014 before a uni-directional (UD) carbon weave skin is applied through the Carbon Structural Integration (CSI) process. To further reduce weight the OS-99 uses a 4-bolt sculpted AL2014 alloy/carbon faceplate and titanium hardware. CSI is a process that permanently bonds carbon to alloy, to create a true hybrid product, with many of the benefits of aluminum and carbon. - Stack Height: 41mm - Weight: 126g (100mm)

- 3D Forged and CNC machined from AL7050/T73 - 3D Forged AL6061/T6 faceplate - 4-bolt cold-forged alloy faceplate - Cr-Mo hardware - 40mm fork clamp stack height - 162g (80mm)

Strong, light, and capable The Kovee Pro 35 stem is the perfect centerpiece for cross country race bike. This lightweight stem is optimized for the latest XC mountain bike standard, with a 35mm clamp diameter that combines with a 35mm handlebar to provide a stronger, lighter system. An oversized 35mm clamp diameter MTB stem that offers increased strength and minimal weight - Oversized 35mm clamp diameter offers increased strength and minimal weight - 7075 T73, 3D, forged alloy construction - Laser-etched calibration marks make dialing in the perfect angle simple and repeatable - Compatible with both Knock Block and standard headsets and spacers - Blendr compatible for an elegant, integrated accessory mounting solution - Available in a wide range of sizes for today's mountain rider - High-strength, corrosion-resistant steel bolts - Approved for carbon bars

A light, durable 35mm MTB stem that adds Blendr capability for clean, integrated mounting of lights or computer. Equip your whip with this 35mm Line Pro stem and give yourself the oversized advantage. Forged from light and strong 7075-T73 3D aluminum, the oversized 35mm design offers increased strength and a lighter overall bar and stem system weight. Use with included Blendr base and mount for integrated mounting options for light or computer. Product details - Oversized 35mm clamp diameter offers increased strength and minimal weight - 7075 T73, 3D, forged alloy construction - Laser-etched calibration marks make dialing in the perfect angle simple and repeatable - Compatible with both Knock Block and standard headsets and spacers - Blendr compatible for an elegant, integrated accessory mounting solution - High-strength, corrosion-resistant steel bolts - Includes Blendr mono base, Garmin Mount, and Ion Light Mount - Approved for carbon bars

The forged alloy construction of the Bontrager Pro Blendr Stem delivers stiffness without compromising its light weight or sleek looks. Easy integration of lights, a computer, and more with the Blendr integration system make this stem a perfect upgrade for any bike. - Pro-level quality 31.8mm clamp diameter stem weighs less than many carbon stems - 4-bolt dual band clamp securely holds handlebar - Uses high-quality M5 corrosion-resistant faceplate bolts with 5.2Nm torque spec - Integrate accessories with included Blendr Pro base and Blendr XXX accessory mounts - Mounts intended for use with Ion and Trip, Garmin, GoPro and SRM accessories - Approved for carbon bars and steerer tubes - Safe installation requires 5mm spacer above and below stem - Included Blendr accessories: Pro Mono Base, Trip Computer mount, and High Ion Light mount

FSA ACR (Aerodynamic Cable Routing) Stems have a low-profile frontal area that is suitable for road and gravel riding. - Aerodynamic Cable Routing (ACR) - Low-profile frontal area - No rotation limit - Body and faceplate - 6061 T6 - Chromoly hardware - Specific frame and headset required - 31.8mm handlebar clamp diameter - 30mm fork clamp stack height - Compatible with: K-Force Light ACR Compact, SL-K ACR Compact, Energy ACR Compact, K-Wing AGX and K-Wing AGX handlebars

The smarter upgrade Outfit your road bike with the Pro Blendr stem to provide confident handling and integrated accessory capability. The forged alloy construction means you'll get the stiffness you demand but in a weight that'll make others jealous. - Pro-level quality 31.8mm clamp diameter stem weighs less than many carbon stems - Blendr technology seamlessly integrates accessories with included Blendr Pro base and Blendr XXX accessory mounts - Blendr XXX mounts include Bontrager Ion and Trip, Garmin, GoPro and SRM accessories - Countersunk, corrosion-resistant steel bolts do not require washers - Approved for carbon bars and steerer tubes - Safe installation requires 5mm spacer above and below stem

Zipp's Service Course SL Stem, crafted from 7075 aluminum, features a shape that's strong and lightweight, resulting in a best-in-class 1.85 grams per newton meter of stiffness. That results in no-flex sprints and accelerations. This stem is a favorite of Zipp ambassadors and pro athletes. - Distinctive Zipp cosmetics - Zipp Quickview integrated computer mount available separately - Lifetime warranty

Hollow stems are cold forged from the highest quality 6061-T6 aluminum available. Featuring an open skeletal design and a dual mid-bolt wedge mounting system, they are lightweight yet maintain a very high level of strength. A 53mm extension stem weighs just 218 grams/7.7 ounces. By removing the rear pinch bolts and moving the mounting bolts to the middle of the stem, we reduced the weight and size and eliminated a serious hazard to the rider’s knees. These stems come with either a 48- or 53mm extension and a 22.2mm bar bore. To ensure proper clamping force, the stem must be mounted on a fork with at least 45mm of exposed steerer tube. Not compatible with forks that have carbon fiber steerer tubes.

Full CNC machined AL6061-T6 alloy construction - 35mm stack height - 4 bolt front loading faceplate design

Make sure your fit is dialed in your race against the clock! Bontrager's Speed Concept Stem allows you to set up your Speed Concept bike for proper ergonomics and aerodynamics. Plus, the precisely integrated design keeps your super aero bike fast and looking pro! - Low-Near = 17° rise / 77mm length - Low-Far = 100° rise / 110mm length - Mid-Near = 50° rise / 67mm length - Mid-Far = 45° rise / 110mm length - High-Near = 80° rise / 67mm length - High-Far = 75° rise / 110mm length

A traditional, lightweight, alloy stem with increased compliance for road and MTB use. Light as carbon. Strong as hell. The super compliant 7050-T6 aluminum alloy Race X Lite bike stem is light enough for the road but strong enough for the mountain. It features a flip-flop 7 degree rise and 31.8 clamp that help it excel in lightweight versatility for a variety of hand positions. - 7050-T6, 3D, forged alloy construction - 4-bolt face plate helps distribute clamping load on ultra-lightweight handlebars - Angled steerer tube clamp spreads clamping pressure on steerer and is carbon friendly - Countersunk, corrosion-resistant steel bolts do not require washers - Dual clamp bolts are strategically positioned to evenly distributing clamping forces - This stem requires at least 5mm of spacers above and below the steerer tube clamp area - Go green and save green – Zero packaging means zero waste and zero extra cost

Full CNC machined AL6061-T6 alloy construction - 40mm stack height - 4 bolt front loading faceplate design - EN-Mountain safety certification

- Full CNC machined AL6061-T6 alloy construction - Designed for use with oversized 35mm handlebars - 35mm stack height - 4-bolt front loading faceplate design - ISO-Mountain safety certified Specifications: - Fork Dia: 1-1/8" - Bar Clamp: 35 - Angle: 0° - Material: AL6061 - Finish: Polished

To meet your urban cycling needs, FSA brings you their Metropolis Stem. It features a clean-looking 2-bolt front-mounted faceplate and is made of 3D-forged aluminum for lightweight strength. The 30° rise puts you in an alert, upright riding position — ideal for navigating city streets. - Stack Height: 40mm - Weight: 180g

Using Odyssey's popular TL48 stem as a springboard, Aaron Ross’ signature BOSS stem is a classic top load design with 52mm of reach and a 35mm rise. FEATURES - Six bolt clamping configuration - Headset pre-load bolt recess (32mm diameter) - 6061-T6 aluminum, CNC machined SPECS - 52mm reach - 35mm rise - 11 oz

The Inverse stem features a CNC'd 6061 aluminum construction with a brushed anodized finish. - Stem Type: Top Load

All Box stems are engineered and crafted using our Oversized Technology. As we follow the load paths down the handlebars we have focused our attention on the stem-to-bar interface. Since the Oversized handlebars have an increased wall thickness and tube diameter in this sector we have reciprocated with an augmented stem interface with greater surface area. We’ve done this by moving material from low stress areas. This has greatly minimized twist and contributed to responsiveness. As the stem in mated with the handlebars we have contributed to increased pedaling stiffness by providing a backstop to the “lifting” phenomenon. There is no point pushing hard on your pedals if you can’t pull up on your handlebars and deliver that power. Power can easily be lost to handlebar-to-stem deflection and the consequences can be poor power delivery and steering control. When combined with Box’s other Oversized components, you’ll experience heightened responsiveness and reduced latency. Key differences: This particular model stem pushes our Oversized Technology to the extreme as it maximizes the shift of material from low stress zones to the Oversized interface. These stems are engineered for the smaller-sized racers. -Lightweight 3D Hollow Design -Front-Load Clamp Design to Fight Pull-Up Forces -Large Bar Bore -Large Hollow Clamping Bolts -Superior Strength

All Box stems are engineered and crafted using our Oversized Technology. As we follow the load paths down the handlebars we have focused our attention on the stem-to-bar interface. Since the Oversized handlebars have an increased wall thickness and tube diameter in this sector we have reciprocated with an augmented stem interface with greater surface area. We’ve done this by moving material from low stress areas. This has greatly minimized twist and contributed to responsiveness. As the stem in mated with the handlebars we have contributed to increased pedaling stiffness by providing a backstop to the “lifting” phenomenon. There is no point pushing hard on your pedals if you can’t pull up on your handlebars and deliver that power. Power can easily be lost to handlebar-to-stem deflection and the consequences can be poor power delivery and steering control. When combined with Box’s other Oversized components, you’ll experience heightened responsiveness and reduced latency. Key differences: In this particular model stem we’ve modulated the Oversized formula to emphasize pedaling stiffness. We have transferred material specifically to sectors that experience sudden stress from pulling up on the handlebars. You’ll feel a difference in your acceleration. These stems are engineered for the larger-sized racers. -Material: 6061-T6 Aluminum -Process: Cold-Forged -Hardware: Chromoly Clamping Bolts -Finish: Anodized w/Laser-Etched Graphics Weight: -48mm: 280 g / 9.8 oz -53mm: 290 g / 10.2 oz

All Box stems are engineered and crafted using our Oversized Technology. As we follow the load paths down the handlebars we have focused our attention on the stem-to-bar interface. Since the Oversized handlebars have an increased wall thickness and tube diameter in this sector we have reciprocated with an augmented stem interface with greater surface area. We’ve done this by moving material from low stress areas. This has greatly minimized twist and contributed to responsiveness. As the stem in mated with the handlebars we have contributed to increased pedaling stiffness by providing a backstop to the “lifting” phenomenon. There is no point pushing hard on your pedals if you can’t pull up on your handlebars and deliver that power. Power can easily be lost to handlebar-to-stem deflection and the consequences can be poor power delivery and steering control. When combined with Box’s other Oversized components, you’ll experience heightened responsiveness and reduced latency. Key differences: In this particular model stem we’ve tailored the Oversized strategy to favor utility and access. The geometry has been altered to allow for easy handlebar removal while at the same time scavenging material from low stress zones. Ideal for those who don’t want to compromise on user experience to gain performance. These stems are engineered for the larger-sized racers.

The Afterburner MTB Stem is 3-D forged and CNC machined from AL6061/T6. You have the option to run this stem at a + or – 6-degrees to suit your racing style. - 3D forged and CNC machined from AL6061/T9 - 4-bolt cold forged front clamp - 40mm clamp stack height - Weight: 149g

Aaron Ross' signature Boss v2 stem is a classic top-load, 6-bolt design. Along with other Odyssey v2 stems, the bolt heads have been upgraded to a larger size and the clamping area features unique surface contouring for superior handlebar grip - Special surface contouring and a larger bolt head spec for superior handlebar grip - Six bolt clamping configuration - Headset pre-load bolt recess (32mm diameter)

The pro from down under, Boyd Hilder, is also getting a signature stem in our lineup, and it's well deserved. Boyd likes the familiar design DNA of our stems, but had specific Specs in mind to suit his all-around riding style. Clean looks, comfortable reach/rise, and a palm tree etching so you can take the beach-y vibes with you. - Boyd Hilder Signature - Unique surface contouring for superior handlebar grip - Six bolt clamping configuration - 6061-T6 aluminum, CNC machined

The Odyssey Broc v2 stem is a refined update to Broc Raiford's popular signature Raft stem. The Broc stem utilizes a classic top-load and 6-bolt design, but it now comes with a slightly taller 33mm rise and sleeker lines below the clamp. The bolt heads have been upgraded to a larger size and the clamping area features unique surface contouring for superior handlebar grip. - Special surface contouring and a larger bolt head spec for superior handlebar grip - Six bolt clamping configuration - Headset pre-load bolt recess (32mm diameter)

Tom Dugan's signature DGN v2 stem is a classic top-load, 6-bolt design. Along with other Odyssey v2 stems, the bolt heads have been upgraded to a larger size and the clamping area features unique surface contouring for superior handlebar grip - Six bolt clamping configuration - Headset pre-load bolt recess (32mm diameter)

Matt Nordstrom Signature edition stem features special surface contouring and a larger bolt head spec for superior handlebar grip. - Six bolt clamping configuration

Great for road or mountain use, the Elite stem features Blendr compatibility to get you and your accessories in the position you need. Blendr Elite allows seamless accessory integration 4-bolt dual band clamp retains stiffness and reduces weight Opposing 2-bolt steerer tube clamp Uses M5 countersunk, corrosion-resistant steel bolts with 5.2Nm torque spec

- Solution for riders wanting to raise their drop bars for added comfort - 225mm tall quill (210mm above the min insertion line) - Forged aluminum - 22.2mm quill - 25.4mm clamp - 386-415g

Basic, clean, and dependable performance—that's the Gossamer stem. 6061-T6 aluminum is forged and then CNC-machined to achieve the Gossamer's shape. The four-bolt faceplate is cold-forged and holds the bars with authority. Laser-etched graphics are the finishing touch. - 3D-forged and CNC-machined from AL6061/T6 - 4-bolt cold-forged front clamp diameter - Chromoly hardware

Origin-8's Fix8 OS Stem is the perfect upgrade for your super-stylish fixed-gear bike and it'll work on mountain bikes, too. It's 3D forged from lightweight and durable 6061 aluminum and features a 4-bolt 31.8mm-diameter handlebar face clamp that holds fast and makes for quick and easy handlebar installation/removal. Plus, the opposing steerer clamp bolts apply more even holding force to keep your bars from changing position. At only 50mm long, the Fix8 is great for flatland tricks, bar spins, and anything else you come up with.

- Ideal for Trail, Enduro, and Downhill MTB applications - 3D forged and CNC machined AL6061-T6 alloy construction - Designed for use with oversized 35mm handlebars - Lightweight, extra-wide 4-bolt front loading one-piece faceplate design - 40mm stack height - Weight: 115g - ISO-Mountain safety certified - Fork Diameter: 1-1/8" - Length: 35mm - Bar Clamp: 35mm - Angle: 0° - Material: AL6061

On today's road bikes, silver stands out amid the sea of stealthy black color schemes. This time-honored color is available on the Zipp Service Course stem. Since the introduction of our line of Service Course and Service Course SL components, we've had amazing success with our pro-level athletes in all disciplines. While the successes have reinforced our design decisions, we have also drawn from their feedback. We not only learned how and why athletes make their equipment choices, but how our manufacturing methods and materials affect product performance. With new knowledge as well as new engineering methods, we are proud to introduce our completely redesigned line of Service Course and Service Course SL stems. - Class-leading stiffness-to-weight ratio - More options for a better fit - New faceplate and geometry for greater stiffness and easier installation - Distinctive silver finish

The Box Two Front Load is a modern, 22.2 stem designed specifically for BMX racing. Box Two Front Load stem bodies are cold-forged and CNC-machined from the highest quality 6061-T6 aluminum. The lightweight front clamps are cold-forged and CNC-machined for increased stiffness and strength. -Material: 6061-T6 Aluminum -Process: Cold-Forged -Hardware: Chromoly Clamping Bolts -Finish: Anodized w/Laser-Etched Graphics Weight: · 48mm: 224 g / 7.9 oz · 53mm: 230 g / 8.1 oz

- 3-D forged AL6061-T6 alloy construction - 40mm stack height - 4 bolt front loading faceplate design

- 3D forged AL6061-T6 alloy construction - Designed for use with oversized 35mm handlebars - 40mm stack height - 4-bolt front loading faceplate design - ISO-Mountain safety certified Specifications: - Fork Dia: 1-1/8" - Bar Clamp: 35 - Angle: 0° - Material: AL6061 - Finish: Matte

Run your favorite 31.8mm clamping diameter handlebar on a bike with Knock Block with the Rhythm Comp 31.8. It adds Knock Block compatibility to a durable stem with multiple lengths to let you fine-tune the fit to your ride. Get 31.8mm handlebar compatibility with your Knock Block system;Also compatible with standard headsets and spacers;Knock Block system protects frame from impacts by fork and handlebars by eliminating over-rotation of bars;Available in a wide range of sizes for today's mountain rider;See Service Parts for other Knock Block parts;

Sunlite's Adjustable Stem adjusts from 0 to +60 degrees so that you can place your handlebars wherever they are most comfortable. It boasts light and durable aluminum construction with steel bolts. It fits on 1- and 1 1/8-inch forks and accepts 25.4mm- and 31.8mm-diameter handlebars too, with included shims. Plus, its 2-bolt clamp makes changing bars easy and holds fast.

Origin-8's Fix8 Stem is a nice upgrade for your super-cool fixed-gear bike and perfect for mountain bikes, too. It's forged from lightweight and durable aluminum and features a 4-bolt face clamp that holds fast and makes bar installation/removal quick and easy. Plus, the opposing steerer clamp bolts apply more even holding force to keep your bars from changing position. At 50mm long, this stout stem is great for flatland tricks, bar spins, and anything else you come up with.

- Lightweight forged aluminum construction - Hidden 2-bolt face clamp - EN Road safety certified - Compatible with 1-inch steerer (22.2mm internal diameter) - Length: 90mm, 110mm, and 120mm lengths - Bar clamp diameter: 26mm - Stem angle: -17 degrees - Steerer length: 140mm

- Ideal for Trail, Enduro, and Downhill MTB applications - 3D-forged and CNC-machined AL6061-T6 alloy construction - Lightweight, extra-wide 4 bolt front-loading one-piece faceplate design - 40mm stack height - Weight: 115g - ISO-Mountain safety certified - Fork Dia: 1-1/8" - Length: 35mm - Clamp Diameter: 31.8mm - Rise: 0° - Color: Black - Material: AL6061-T6

Highline topload stem, forged 6061 Aluminum construction. - Bar Clamp Diameter (mm): 22.2 - Reach: 50 mm - Rise: 35 mm - Steerer Clamp Diameter: 1-1/8" ins - Stem Type: Top Load

3-D forged AL6061-T6 alloy construction - 40mm stack height - 4 bolt front loading faceplate design

- Available in a variety of lengths, angles, and bar bores for the perfect fit - Road or Mountain compatible - 3D forged AL6061-T6 alloy construction - 40mm stack height - 4-bolt front loading one-piece faceplate design - ISO-Mountain safety certified

With its alloy/steel construction and 4-bolt clamp design, the Freestyle is a trusty BMX quill stem. - Hollow-core stem bolt - Quill Length: 4-1/4-inches - Quill diameter: 21.1mm

- Adjustable top mounted threadless stream - Adjustable from 0 to 60 degrees - Available in two lengths - Material: Alloy

Origin-8's X-Tra Lift Stem Riser is an adapter that lets you raise your handlebars and stem. It fits over and securely bolts to 1 1/8-inch forks to extend them. This gives you more height to raise your stem/bars. You use the included spacers to dial in the best fit. The Stem Riser is made from forged 6061 aluminum and is anodized for durability.

Origin-8's Pro Fit Alloy Ergo Stem is a great upgrade for road and mountain bikes. It's 3D forged from lightweight and durable 6061-T6 aluminum. It has a 4-bolt, 2-piece face clamp that shaves grams and makes for quick and easy handlebar installation/removal. Plus, the opposing steerer clamp bolts apply more even holding force to protect the fork and keep your bars from changing position.

Genuine replacement parts Get back on the road with a genuine replacement stem. For optimal adjustability. - High-quality alloy adjustable stem is compatible with threadless forks - Features 64-degree angular adjustment for a wide range of fit needs - 4-bolt dual band clamp retains stiffness and reduces weight - Blendr ready for seamless accessory integration - Compatible with Blendr Comp & Legacy Elite bases and mounts, sold separately - Other parts are required to install this on a bike, you will be prompted to add the appropriate parts to your cart along with this item

Oversized diameter 35 mm stem accessible to all mountain riders. Oversized and in control Equip your whip with this 35mm Line stem and give yourself the oversized advantage. Forged from 6061-T6 3D aluminum, this 0-degree stem provides the increased strength of the latest mountain-specific bar diameter. Product details - Oversized 35mm clamp diameter provides a new level of strength and weight savings - Forged from 6061-T6 3D aluminum - Laser etched calibration marks make dialing in the perfect angle simple and repeatable - Compatible with both Knock Block and standard headsets and spacers - Knock Block system protects the frame from impacts by fork and handlebars by eliminating over-rotation of bars - Available in a wide range of sizes for today's mountain rider - Safe for carbon bars

- Steerer Diameter: 1" or 1-1/8" (includes shim) - Length: 70, 90, 110mm - Bar Clamp: 25.4 or 31.8 (includes shim) - Angle: +/- 35 degrees - Material: 6061 Aluminum - Shot-peen finish

- Forged AL6061-T6 alloy construction - Matte finish with laser-etched graphics - ISO-Mountain safety certified - 4-bolt handlebar clamp - Quill length: 180mm

• Forged aluminum • Single-bolt clamp • 180mm tall

The Treymone stem features a 51mm reach and a 27mm rise. - Trey Jones and Simone Barraco signature - Heat treated cro-mo M8 6mm solid hex bolts - Cold forged & CNC machined 6061-T6 Alloy

- 3D forged 6061 alloy road stems in 6 or 17 degree angles - Lightweight 4 bolt faceplate - Material: AL6061-T6 - Finish: Sandblasted

• Forged aluminum • Anodized finish • 2-bolt clamp • 150mm tall