The British Army adopted it in 1935 following extensive trials of the Czech ZB vz.26 light machine gun which was manufactured in Brno, although the ZB vz.26 was not actually submitted for the trials, a slightly modified model was submitted; the ZB vz. 27. A licence to manufacture was sought and the Czech design was modified to British requirements. The major changes were in the magazine and barrel. The magazine was curved in order to feed the .303 British rimmed cartridge, a change from the various rimless Mauser-design cartridges used to date, such as the 7.92 mm Mauser round. These modifications were categorised in various numbered designations, ZB vz. 27, ZB vz. 30, ZB vz. 32, and finally the ZB vz. 33, which became the Bren. The Bren name was formed as a contraction from "Brno" and "Enfield" (the Royal Small Arms Factory, or RSAF, in Enfield, where it would be manufactured).
The Germans also used favorably,
When germany occupied czechoslovakia in march 1939, the ZB 1926 was incorporated into the german army under the designation MG 26(t), the suffix (t) denominating a captured weapon of czech ("tschechisch") origin. Together, the germans aquired 31,204 machine guns of the types ZB 1926 and it's successor, the ZB 1930. Another source for these weapons were those captured in Yugoslavia that had originally bought 1,500 ZB 1926, although it is unknown how many of these exactly were captured by the germans.
The MG 26(t) is an air-cooled, gas-pressure operated fixed-barrel machine gun. The necessary gas pressure is taken from a little hole drilled into the barrel near the muzzle and activates a gas piston that opens and moves the breech block, the empty cartridge case is ejected. The loading of a new cartridge and the locking of the breech in the firing position is then done via a strong recoil spring. Although the weapon is viewed by many experts as one of the light machine gun designs, it has the distinct flaw of a too small amount of ammunition because of the use of magazines which only contained 20 rounds.
The weapon by design had always been in the german caliber 7.92mm Mauser; it can be fired both in semi- and full-automatic mode. The weapon used straight or curved magazines inserted from the top that weighed 0.8kg when fully loaded with 20 rounds; the sights of the weapon ranges from 200m to 1,500m in increments of 100m.Other data: Length 116.5cm, barrel length 60cm, rate of fire 520/min, weight 8.9kg (empty = without ammunition), V0 = 760 m/s.