Aluminum Alloy Bicycle Seatpost 100mm

I needed a 30.9mm to 34.9mm sleeve for my Specialized Como 3 bike. The most appropriate shock absorbing post was not available in the 34.9mm native size so I needed an adaptor and chose this one based on the reviews and pricing. The sleeve is an anodized precision, machined aluminum unit that has a slit along the entire length. There is a retaining ring on the top of the sleeve and the surface has a scored surface that helps retain a grip around the inside and outside of the sleeve. I found that a light coating of lithium grease on the outside of both the sleeve and the shock post allowed the sleeve and post to be more easily inserted into the bike frame. This is a very high quality adaptor and was better than I expected. It works well and is precision made.

So far so good

Fits well and stays in place.

Once you get correct measurements this little device perfectly solves the problem. I needed a new seat post to get more elevation on my seat and the new post was too narrow, so with this shim the new post works just fine.

This diameter conversion sleeve allowed me to reuse a seat post that I already had in stock, but it didn't save a lot of money.

A great way to use a dropper post that is a little small(diameter) for the frame.

It worked perfectly well after adjusting the tube in my bike.If you are going to buy one of these, as there are so many options, make sure you measure the diameters of the tube in your bike and of the seat post using a precision caliperI mean a caliper with a digital readout measuring down to a hundredth of a milimeter.Keep in mind that you can reduce the tube of your bike by .1 or .15 of a milimeter, but you cannot enlarge it!

Take a file and grind a chamfer on inside radius of top flange as shown in pics. For good measure a filed a chamfer with square file down the slor as well. When I first installed the collar I noticed small flakes from my post where the sharp edges were digging into my post as it flexed.

What I liked best besides the fact that it fit perfect is in the description it was mentioned what size to go by considering the post youvare working with. The shim is well made and does exactly what it is supposed to.

Works well, does what it's supposed to.

Worked well to adapt a 31.6mm suspension seatpost to a 33.9mm tube.

Works as it should.

works, period.

This adapter worked perfect for my bike. I wanted to put my cruiser suspension seat post on my new bike and this adapter works great with no issues.

It fit perfectly no issues great product.