Fotodiox 55mm Filter Thread Macro Reverse Mount Adapter Ring for Sony Alpha A-Mount (and Minolta AF) Mount SLR Camera Body Reverse mounts optics with a 55mm filter thread to Sony Alpha A-Mount (and Minolta AF) Mount SLR Cameras Extreme macro close-up results All-metal design; hardened anodized aluminum construction Premium grade Fotodiox adapter 24-Month Fotodiox warranty