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Functional bling for your cockpit.

Most riders don't consider their seatpost collar on day-to-day rides—until their seatpost starts to creep down halfway through some epic ride due to a poorly constructed collar. The Thomson Seatpost Collar not only alleviates your underperforming seatpost collar woes with its powerful clamping force, but it also adds serious bling to your cockpit with its anodized black or shiny silver finish.

  • Aluminum with anodized black or silver finish
  • 1.5-degree off-center threaded bolt
  • 18-gram weight

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Here's what others have to say...


It's the little things...

  • Familiarity:I've used it several times

Seat collars are simple and only have one job-keep your post from slipping. It is surprising how often something as simple as a seat collar is done badly. Either the collars don't keep the post in place or the collar itself is susceptible to breakage.

The Thomson collar will not let you down. It is light, it is dependable and elegant. I would say that this simple collar design and finish boards on usable art.

Upgrade your bike now!


Clean and good looking

    Got this to replace one that came on the bike. This one looks good on the bike and feels solid. You can 't go wrong with this.

    is the measurement referring to the inside...

    is the measurement referring to the inside diameter? my bike seat tube is 31.8 internally so the seat post clamp should be the larger diameter?

    The measurement does refer to the inside diameter, which is the outside diameter of the seat collar.


    That added bling

    • Familiarity:I've put it through the wringer

    Thomson Post?-Check

    Thomson Stem? Check

    Thomson Bars?-(YEP they make bars!) Check

    Thomson Seat Collar?- NO?!?! What is this, amateur hour? Add that added bit of bling, you know you want to, your bike will thank you.


    Solid piece, set it and forget it

      Would have given this a 5 if it was a little lighter or a little more economical.

      Lets be honest, the only reason 95% of us upgrade from stock is to save weight or add bling. This part is anti-bling but lighter than your average QR factory clamp, but I replaced it on my latest build with a titanium unit weighing 10g that was half the price, so.....

      Unanswered Question

      If my frames seatpost size is 27.2mm ,what...

      If my frames seatpost size is 27.2mm ,what would be the normal clamp tube size?

      I need a clamp for a 63CM Serotta (road...

      I need a clamp for a 63CM Serotta (road bike) w/ a Ti frame - 31.8. I’m using a Thompson 30.9 seatpost, will this fit the fame and clamp down the post?

      Is there a return policy?

      Hey Doug. I don't think the 31.8 will fit your bike. I think you need a 34mm but you could measure the outside diameter of your seat tube if you have calipers and it will give you a number close to what size you will need. Bear in mind we are work in very small increments so you will need to be precise. Aluminum frames with 31.6 seatposts usually run the 35mm clamp but since you have a Ti frame and a 30.9 seatpost you are going to need something in the 44mm range.