Product Description
The Trek Domane Gen 3 Carbon Internal Seatmast Cap is a lightweight, color-matched replacement for compatible Trek Domane SL, Domane SLR, and select Domane+ models using the Gen 3 internal seatmast system.
Ultra-light carbon construction maintains the clean appearance and performance of the original cockpit, while multiple length and offset options allow the rider to match the original fit or adjust saddle positioning.
This is a multi-variation listing with options in 155mm or 200mm length, 5mm or 20mm offset, and Gloss Viper Red or Gloss Black. Please select the exact configuration required for your bicycle.
Key Features
- Genuine Trek replacement seatmast cap
- Designed for the Gen 3 Domane internal seatmast system
- Ultra-light carbon construction
- Available in 155mm and 200mm lengths
- Available with 5mm or 20mm offset
- Color-matched Gloss Viper Red and Gloss Black options
- Aero-shaped internal seatmast design
- New and retail packaged
Variation Options
Gloss Viper Red
- 155mm Length / 5mm Offset
- 155mm Length / 20mm Offset
- 200mm Length / 5mm Offset
- 200mm Length / 20mm Offset
Gloss Black
- 155mm Length / 5mm Offset
- 155mm Length / 20mm Offset
- 200mm Length / 5mm Offset
Specifications
- Brand: Trek
- Product Type: Carbon Internal Seatmast Cap
- Frame Platform: Domane Gen 3
- Length Options: 155mm / 200mm
- Offset Options: 5mm / 20mm
- Material: Carbon
- Finish: Gloss
- Color Options: Gloss Viper Red / Gloss Black
- Saddle Rail Clamp System: Interchangeable clamp ears sold separately
Choosing the Correct Size
155mm vs. 200mm Length
- The 155mm option provides the shorter saddle-height range
- The 200mm option provides additional height for riders requiring a taller saddle position
- Match the original seatmast length whenever possible
5mm vs. 20mm Offset
- The 5mm offset places the saddle farther forward
- The 20mm offset provides greater saddle setback
- Choose the offset that matches the original seatmast or required bike fit
Changing the length or offset can affect saddle height and rider position. Do not select solely by frame size.
Compatibility
Designed for compatible bicycles using the Trek Domane Gen 3 internal seatmast system, including applicable:
- Trek Domane SL Gen 3
- Trek Domane SLR Gen 3
- Select Trek Domane+ electric road bikes using the same seatmast interface
This is not a universal seatpost and should not be assumed compatible with earlier Domane generations, Domane Gen 4, or every Domane+ model.
Please confirm:
- Bicycle model and model year
- Gen 3 frame platform
- Original seatmast shape
- Required 155mm or 200mm length
- Required 5mm or 20mm offset
- Required color
- Saddle rail clamp-ear type
For Domane+ e-bikes, verify fit using the bicycle serial number or Trek replacement part number before ordering.
Saddle Rail Compatibility
The saddle rail clamp ears are sold separately.
Compatible clamp ears are available for applicable:
- 7x7mm round saddle rails
- 9/10mm oval saddle rails
The correct clamp ears must match the saddle’s rail dimensions. Existing clamp ears may be reusable when compatible and undamaged.
Included
- One Trek Domane carbon internal seatmast cap in the selected length, offset, and color
- Includes only what is pictured and described
Warranty and Notes
- Genuine Trek replacement component
- This is a multi-variation listing
- Carefully select the correct length, offset, and color
- Saddle rail clamp ears are not included
- Carbon assembly compound and proper torque procedures should be used as specified by Trek
- Professional installation and bike-fit adjustment are recommended
Condition
- New
- Genuine Trek product
- Includes only what is pictured and described
