Fotasy 37-40.5mm Stepping Up Filter Ring Adapter This 37mm-40.5mm step up adapter ring allows a filter attachment with larger thread size (55mm) to be used with a lens with smaller thread size (52mm). To the side of Lens (Male Thread): 37mm To the side of Filter (Female Thread): 40.5m Material: Metal, Color: black Work for 40.5mm Filters, Lens, Lens hood, Lens cap, etc.