Simple set of scope shims. 0.5 degree drop for 2 piece scope mounts where the leg of each mount is 20mm long and they are spaced 60mm apart. Designed to still keep the clamps square, so the scope won't be damaged by being at a slight angle.

There is 1 slightly taller shim, to be placed on the bottom, at the front or back, depending if you want to raise or lower the scope angle. The other 3 shorter shims are sized identically and are used to keep the mounts clamping down square against the (now) angled scope. Pay careful attention to which way round you place the shims, to accommodate the angle. The difference is only very slight, so look carefully.