The gun B-20 (20-mm) has been created by M.E.Berezin in 1944 on the basis of its 12,7-mm of machine gun UB without any design changes, by a replacement of a trunk.
   The cannon was created under ShVAK cartridge. As an ammunition all nominal ammunition of automatic control unit ShVAK were applied. Charge pneumatic or mechanical.
   Weight of a gun of 25 kg. Rate of shooting for synchronous version 600 of shots/minutes, for turret and wing - 800 shots/minutes.
   Weight of a shell 96 g, an initial missile velocity of 800 m/s.
   The cannon was established on Il-2, Yak-1, Yak-ÇP, Yak-7B, LaGG-3, La-5, La-7, Tu 2 and Il-10 aircrafts.
   Per 1946 there was to manufacture an electrified version B-20E for towers where it was established before acceptance on arms of NP-23 cannon.
   In 1944 2275 B-20 cannons, in 1945 - 7240, in 1946 - 440, in 1947 - 780, in 1948 - 1686. in 1949 - 2931 have been made. On it manufacture of them has been stopped.