you can OEM about the Size
Substrate:Optical glass

The 890nm Narrow Bandpass Filter

Size:square,circle or OEM

CWL  = 890nm+/-5nm

FWHM = 30nm +/-5nm

T>90% @ 890nm

T<1% 300-1100nm (outside bandpass)

Size: square,circle or OEM

Thickness: 1mm

Scratch-dig: 60/40

 Material;HWB830(RG830) or opticals glass.