... 37-30mm,37-34mm,52-58mm,55-58mm,etc. camera accessories lens adaptor step ring Step rings have different size ... and step-down adapter ring for your selection.Camera adapter ring is used between camera(or projector) and lenses ,it could mount ... ,and so on.Adapter rings are labeled form the camera to the filter.They're made of metal-aluminum ... 52-58mm,55-58mm,etc.Adapter ring /Lens adaper /Camera adapter