u/Due_Tailor1412

https://preview.redd.it/ed0t6o0fy12h1.png?width=1808&format=png&auto=webp&s=808c96b41b1577d0b11ac32f41a71d3c69d23732

A friend has bought this lens and asked me to identify the mount .. it's a carl Zeiss Jena Biotar .. which made me thing Exa or Exacta ? However I know someone here will know !

https://preview.redd.it/c1fewm1jy12h1.png?width=1808&format=png&auto=webp&s=76eea1a8ef45349e47e74abe684adc6e27d275d4

https://preview.redd.it/qhyb4aboy12h1.png?width=572&format=png&auto=webp&s=f8b71fdb3b4e41beb85675670f136d561db2dfcf