This 137mm Gun Star Picatinny Titled 20 MOA base/adapter is ideal for precise long range shooting with an upward tilt/cant angle of 20 MOA. This base features recoil resistance, heat treated steel with a blued finish, and is guarantee to return to zero after remount. This base has a very low mount, 10 picatinny recoil grooves, and is compatible with all firearms with a Blaser R93, R8, LRS2, K95, and S2 saddle mount system. Gun Star® We take pride in precision Gun Star Picatinny 137mm Tilted 20 MOA Base for Blaser GS-Blaser-7