Filters are designed by their manufacturers to transmit or absorb different wavelengths of light. And they are widely used in scientific experiments and industrial applications where that change is necessary. Color Separation Filter,Neutral Density Filter,Filter,Short/Long Wave Pass Filter,Bandpass Filter and Interference Filter Specification of our color filter as follow: Material:Filter Glass,BK7 Dimension: 4mm-160mm - 0.20mm Squares/Rectangles:1mm-165mm Thickness:0.5mm-4mm Thickness tolerance:+/-0.01mm-0.1mm Paralism: Up to 3 Arc minutes Edges:Fine Ground Flatness:Up to Lambda/10 Surface quantity: 80/50-20/10 Scratch/Dig