The Seco Walleye Prism System accommodates a full size 62 mm prism for long range applications or when a larger prism is needed. Features include a -40 mm offset, ± 2 mm, ability to pivot in two axes, and a stainless-steel locking type. Plus, this prism has a rain hood that helps keep the prism clean to ensure continual measurements over a long measuring cycle. The flat bottom of this L-Bracket measures 2.3 x 3.4 inches with five holes suitable for mounting to a variety of surfaces. It also has a center pivot hole which measures 3/8-inch and four screw holes with 11/64-inch outer diameter. The system is compatible with all M20 screw-in type prism canisters.