The 220FIB12 from Knight Optical is a UV Interference Band-Pass Optical Filter that has a central wavelength of 220 nm. It has an average wavelength blocking range of 200 to 1150 nm with OD4 (0.01%) optical density tolerance. This optical filter has a peak transmission of 16% and FWHM of 14. It has an 8.5 mm aperture with a bandwidth of 14 nm. This optical filter is available in a hermetically sealed package mounted in a black anodized aluminum ring that measures Ø12.5 x 6.1 mm.