Specification:

*Material BK7 or UV grade fused silica
*Dimension Tolerances +/-0.1mm
*Clear Aperture >80%
*Surface Quality:60/40 Scratch/Dig
*Surface Flatness lambda/4 at 633nm
*Angle Tolerance 60 degree+/-3 minutes
*Chamfer 0.3mm+/-0.1mm
*Coatings Optional