Lee 100 Solid ND ProGlass IRND Filter - 15 StopsThe Lee ProGlass 100 mm IRND 15 stop filter offers neutral density filtration of 4. 5, giving the user even more control over the exposure of their image. ProGlass filters are made from 2 mm thick glass. Key Features: Lee ProGlass IRND 100mm 15 stop filter Manufactured under the legendary Lee name: IRND filters are made from high quality, 2 mm thick glass Used by the pros: Lee Filters are used by professional photographers and cinematographers at the