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Item # THP0008

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  • Select options
  • Black, 28.6mm ($30.00)
  • Black, 31.8mm ($30.00)
  • Black, 35mm ($30.00)
  • Silver, 28.6mm ($30.00)
  • Silver, 31.8mm ($30.00)
  • Silver, 35mm ($30.00)
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Item # THP0008

A functional piece of bling to top off your Thomson cockpit.

Thomson has a fitting reputation for reliable, functional and lightweight components. In the same vein as Chris King, they take their time before releasing a product -- when they do, they've done it right. The Thomson Seatclamp is no different. Granted, most of us don't consider a seatclamp a performance component -- that is, until it's not performing. There's not much worse than being on a ride when your seatpost is gently easing its way down into the seat tube.

The Thomson Seatclamp represents the Thomson values in a sleek, simple, lightweight package. While they admit you probably won't win a race because of it, Thomson engineered this beauty to perform -- the bolt is threaded at an angle, about 1.5 degrees off-center, to help provide awesome clamping force -- they say just 20 inch-pounds on the fastener will suffice. It's available in anodized black or silver in 31.8 or 35.0mm sizes.

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

Tech Specs

Claimed Weight:
18 g
Recommended Use:
road cycling
Manufacturer Warranty:
5 years

Community & Reviews

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Thomson Seatpost Collar

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Here's what others have to say...

5 5

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.

Unanswered Question

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?

Avg. ride time: 1h 15m per week
  • Average ride time is based on Strava activity over the last 3 months. Give your reviews credibility by connecting your account.
5 5

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.

4 5

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?

Responded on

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.