This prism assembly allows the user to quickly adjust the tilting target from behind the prism as it is pointing to the instrument to allow accurate sighting. The targets are 5½ x 7 in. The prism can be either mounted in a 0 or -30 mm offset position. All come with a protective carry case for the target or complete system. The complete prism systems come with a 62 mm silver-coated prism in a sealed canister.