Trek Colour-Matched Carbon Seatmast Cap & 7 mm Round Ears

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Trek Colour-Matched Carbon Seatmast Cap & 7 mm Round Ears

Model 559538

Offered in white and black and a variety of lengths and offsets, the mast cap includes hardware compatible with round saddle rails only. 7x10mm carbon rail-compatible hardware sold separately.

Product details

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

greylight-0 swatch

Bontrager Rotary Head Seatpost 7 x 9 mm Saddle Clamp Ears

$27.99

black-0 swatch

Bontrager Aeolus Elite Bike Saddle

$229.99

black-0 swatch

Bontrager Flare RT Rear Bike Light

$99.99

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	135 mm	135 mm	175 mm	175 mm
Offset	5mm	20mm	5mm	20mm
Rail compatibility	7 mm round	7 mm round	7 mm round	7 mm round
Material	Carbon	Carbon	Carbon	Carbon
Weight	130g	130g	150g	150g

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, colours, materials and pricing. Due to supply chain issues, compatible parts may be substituted at any time without notice. The prices shown are the manufacturer's suggested retail prices.

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