Seat clamp

• To select the correct size Circuit Clamp for your frame:

1. We recommend using a caliper to measure your frame’s seat-tube outer diameter
2. Please note: Seatpost Clamp sizes DO NOT match Seatpost sizes
3. Please refer to your frame manufacturers specifications for recommended Seatpost Clamp size
4. Or email us for help determining what size you need

It is probably 34.9/35mm (they can be used interchangeably).

I wasn't able to find the size on the Torque product page which is kind of weird that they don't list what it actually is, lots of other information but not that one.

To be sure you should measure the outer diameter of the seat post near where your current seat post collar is.

It may be marked on the old clamp somewhere if you're lucky.