Check the listing for details. 40.5mm-37mm Metal Step Down Ring Camera Lens Filter Adapter Ring Aluminum Filter. Condition: New. Listed at 11.71 USD. The camera lens adapter ring can be installed in front of the lens, allowing you to use filters and accessories different from the size of the camera lens. The adapter ring can change-over lenses of various sizes, so that you can share the same filter, shutter, additional lens, etc.SpecificationColor: BlackMaterial: Aluminum AlloySuitable for: all 40.5mm lenses and 37mm filtersOverall Size: 44x5.5mm/1.73x0.22inch(Dia.H)Male Thread: 40.5mm/1.59inchFemale Thread: 37mm/1.46inchPackage List: 1 x Filter Adapter Step Down RingAdvantageThe adapter ring is made of aluminum alloy and coated with matte black electroplated coating, which can resist corrosion and other wear elements often encountered in outdoor photography.