"OPTICAL GLASS FINE ANNEALED,MIL-G-174;ALL SURFACES SHALL BE POLISHED EXCEPT BEVELED EDGES WHICH SHALL BE FINE-GRAY GROUND;ANTI-REFLEC TION COATED;BEAMSPLITTER COATING; 5.480 IN. OA LG;BOTH SIDES BEVELED 1.410 IN.;BOTH SIDES TAPERED TO 5.280 IN.;3.740 IN. OA WD"