We’ll make this a great experience

It’s our mission to provide you with world-class hospitality every time you visit us online or in-store. We’ll always take care of you. It’s the Trek way.

Awesome free shipping options

All accessory orders over $49 ship to your home for free, and all accessory orders ship free to your local retailer for in-store pickup.

30-day Unconditional Guarantee

If for any reason you’re not 100% happy with your online order from trekbikes.com, you can return it in like-new condition within 30 days. No questions asked.

Learn more

Trek Color-Matched Matte Carbon SeatMastCap & 7mm Round Ears

Model W600908

Trek-compatible seat mast cap.

Product details

Ultra-light carbon construction
Direct fit on all Trek road bikes with round seat masts
Color matched for direct compatibility
One bolt head design offers easy fore-aft and infinite angle adjustment
Includes 7mm round saddle clamp ears, 10mm ears sold separately

"Lower weight and increase stiffness without the inherent drawbacks of fully integrated seatposts"

"As well as saving weight, it can flex more than in a traditional system"

"A new level of component integration for Trek"

"Trek took the extra step of making long and short seat mast tops available for personalized sizing"

Get all your favorite apparel from over 80 of the world's best cycling brands delivered right to your doorstep or local Trek retailer when you shop our curated online collection. If you're not 100% satisfied, you can return your purchase within 30 days for a full refund.

Shop all gear

If for any reason you're not satisfied with a Bontrager or Trek aftermarket purchase, return the item, along with the original sales receipt to the original place of purchase within 30 days for an exchange or refund. Think of it as a 30-day test ride.

Learn more

Size	135mm x 5mm	135mm x 20mm	175mm x 5mm	175mm x 20mm
Length	135mm	135mm	175mm	175mm
Offset	5mm	20mm	5mm	20mm
Rail compatibility	7mm round	7mm round	7mm round	7mm round
Material	Carbon	Carbon	Carbon	Carbon

We reserve the right to make changes to the product information contained on this site at any time without notice, including with respect to equipment, specifications, models, colors, materials, and pricing. Due to supply chain issues, compatible parts may be substituted at any time without notice. Prices shown are manufacturer's suggested retail prices.

Weights are based off pre-production products at time of publication. Weights may vary in final production.