The Type VIIC was the workhorse of the German U-boat force, with 568 commissioned from 1940 to 1945. The first VIIC boat commissioned was the U-93 in 1940. The Type VIIC was an effective fighting machine and was seen almost everywhere U-boats operated, it had a range of 8,500 nautical miles.
It's deck gun couldn't be used against aircraft, and was only used against unarmed and lonely merchants, and was removed in most ships during 1943 to improve underwater speed.