LEICA Super-ANGULON-R 1:4/21mm Ultra-Wide-Angle 21mm F4 Lens by LEITZ Wetzlar
Ultra-Wide-Angle Lens by LEITZ Wetzlar 3-CAM Version. The original LEITZ Wetzlar Germany R 1:4 21 XIII/XIV 12506. LEICA Super-ANGULON-R 1:4/21mm. lens hood is listed under the following link.