Material:BK7 A glass, Quartz, CaF2,crystals or others Parallelism:1 Are min Clear Apenture:90% Squares/Rectangles:1mm-110mm+/-0.2mm Center thickness tolerance:+/-0.1mm Surface quality:60-40-20/10 Scratch/Dig Surface flatness:lambda/10 at 632.8nm Parallelism:1 Are min
