Mamiya Automatic Extension Ring Number 2 is designed to extend the lens 23.6mm from the camera body. This set is designed for use with 80mm f/1.9 and 80mm f/2.8 lenses. Its diaphragm automation and meter coupling are preserved when coupled to lens. When combined with Number 2 and 3 extension rings 80mm lens enables full 1:1 ratio. Individually the extension rings extend the lens either 11.8mm (No. 1 ring), 23.6mm (No. 2 ring) or 35.4mm (No. 3 ring) from the camera body.