Thomson

29.8 Seatclamp

What Our Gearhead® Experts Are Saying:

"I run the 29.8mm Thomson collar on my alloy hardtail and it’s rock solid. The clamping force is super consistent even at low torque, and it matches my Thomson post and stem for a dialed, clean look. It’s that classic Thomson craftsmanship—simple, strong, and made to last."

A seatpost collar may seem simple, but when it’s a Thomson, it completes the build. The 29.8mm Thomson Seatpost Collar is crafted in the USA from the same high-grade 7000 series aluminum as their iconic posts and stems. Paired with a precision-machined fit and trusted hardware, this collar offers an unbeatable blend of light weight, strength, and long-term reliability.

We trust this collar not just because of its heritage, but because it works flawlessly. The offset slot and barrel nut design provide even pressure distribution without over-torquing, so we get a perfect hold with just 2.8 Nm of torque. Whether it’s securing a dropper or a fixed post, the 29.8mm Thomson collar delivers minimal fuss and maximum hold—exactly what we want from our cockpit.