Shakespeare 414 shims kit for ratchet mounts - heavy duty rubber.
Set of four shims, two with each face/back and side/side slope.
Each shim adds a half "notch" (5°) of tilt.
Stack them for extra height or for compound angles.
Overview:
Strong rubber
Kit with 4 shims, 2 side-to-side and 2 front-to-back