The original design however, was from Czechoslovakia and this version was designated the ZGB. The Bren was a large gun weighing in at 25 lbs fully loaded and had an overall length of 42 inches. The Bren could also be fitted with a bipod, although it could also be mounted on a tripod or vehicle-mounted. The gun came chambered in the British .303 round and later would be rechambered to fit the 7.62x51mm NATO round after the end of World War II. The box magazine at the top of the gun has a round capacity of up to 30 rounds and it also had a rate of fire of about 500 rounds per minute.