Well Equipped
The submarine had two propellers that worked with the help of four electric motors charged by a quarter of diesel engines. The listed crew consisted of 54 men and six officers but in the 1944 announcement, 80 members were reported missing.
January 31, 1941
The Grayback was fully stocked with equipment like ten 21-inch torpedo tubes, with six directed to the bow and four at the back. It was also equipped with a 50 caliber machine gun and Bofors 40 mm and Oerlikon 20 mm cannons that were all mounted on the deck.