The 550FIR50 from Knight Optical (UK) Ltd is a Optical Filter with Wavelength 530 to 570 nm, Center Wavelength(CWL) 550 nm, Bandwidth (FWHM) 40 nm, Blocking Wavelength 200 to 1150 nm, Filter Diameter 50 mm. More details for 550FIR50 can be seen below.