Trek Round Seat Mast Cap

Trek-compatible seat mast cap Matte Onyx

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.

Key features:

- Ultra-light carbon construction
- One bolt head design offers easy fore-aft and infinite angle adjustment
- Compatible with all Trek road bikes with round seat masts
- 175mm and 135mm lengths
- 5mm and 20mm offsets
- Aluminum clamp