Specification:
Material: SF11 grade A optical glass or BK7 grade A optical glass
Dimension Tolerance: +0.0, -0.2mm
Clear Aperture: >85% of diameter
Angle Tolerance: <3 arc minutes
Flatness: lambda/2 at 632.8nm
Surface Quality: 60-40 scratch and dig
Deflection Model: 180° deflection(Standard)
Coating: R<0.25%  at 1550nm on big face(input and output at the same face)
Bevel: 0.25mmx45deg