An extremely rare Carl Zeiss Jena 4cm (40mm) f/2 Sonnar, originally made for the premium Tenax II cameras.
Lens was rehoused and converted to Leica M with full RF coupling. Lens can focus from Infinity down to 0.7m using the RF system on Leica M3, M2, M4, M5, M6, M7, M8, M9, M10, M11…etc
Lens covers the full frame and is one of the widest-fastest sonnars made (35mm & 38mm versions are usually f/2.8 and modern 40mm version f/2.8 also). Very few of these lenses were made.
This is an uncoated version. It has bespokely made conversion mechanics. During service, we took the liberty of black matte flocking the inside walls of the lens for maximum contrast/ flare resistance. It comes with an S35.5 front UV filter and a push on metal cap, and rear M cap.