The PCX-FS-025-250 from Artifex Engineering GmbH & Co. KG is a Optical Lens with Wavelength Range 587.6 nm n=1.45848, Focal Length 248.142 to 250 mm, Center Thickness 2.71 mm, Diameter 25.4 mm, Radius 114.62 mm. More details for PCX-FS-025-250 can be seen below.