Clearance. Black housing. CST/berger 63-2011 2 1/2" (62.5mm) polycarbonate prism in canister is designed as the replacement prism for the CST/berger 63-2010(M) Universal Prism assembly, or the CST/berger Optima Series Prism assembly. However, it will fit any prism assembly with a M20x2 thread.
Clearance CST/berger 63-2011 Polycarbonate Prism in Canister