The Problem Solvers Seatpost Shim is what you need when your seatpost is a little too small-diameter to fit tightly into your frame. It's made of light, durable aluminum and has a lip on the top so it won't slide down inside the frame during installation.
|2.2mm shim, 27.2 seatpost to 29.4 frame||708752009905||ST0222||210000014328|
|3.0mm shim, 27.2 seatpost to 30.2 frame||708752011519||ST0230||210000014330|
|4.4mm shim, 27.2 seatpost to 31.6 frame||708752012875||ST0244||210000014336|