Sof' Shoe Shim solves angular soft foot alignment problems on motors, pumps, generators, turbines and other plant machinery in minutes. It is made of a proprietary elastomer which has unique flow and set characteristics to fill irregular gaps. Yellow Shims are .045" thick and compress to .040". Blue Shims are .020" thick and compress to .0175". The thickness tolerance of Sof' Shoe Shim is .005". Pieces per package = 10.