Fotodiox 10-LA-MR-PK-49 49MM Filter Thread Macro Reverse Mount Adapter Ring for Pentax K Camera Fits Pentax
By mounting the lens backward on a camera body, you can create amazing macro images. It is extremely fun to turn you lens into a macro lens. You can mount lenses with 52mm filter thread size of any brand. It will be more fun to use on lenses with aperture dial to adjust aperture.