Special macro lens for the FED 1938/1939 production. This special lens is not rangefinder coupled but goes from infinity up to 1:1 scales in continuous focusing.
The optics is the renowned Industar 10 3.5/50.
Non numbered macro lenses can be found. According to some sellers, they could have been made in 1949 or 1950.
At least two pre war series were made: with pins (written 1st on the list) and without (written 2nd). Probably to help the owner to screw or unscrew the lens...
Registered serial numbers:
3-------------Jacques coll. 1st.
107----------DVD. 1st.
12075-------seen on eBay. 1st.
13923-------AlexanderK
14049-------Juhani 2nd
14568-------Jacques coll. 2nd.
14764-------Alain Berry collection. ?.
14875-----no pins---imcphoto collection
15136-------DVD collection. 2nd.
15343-----no pins---Jim McGee
15446-------David Tomlinson. 2nd.