In terms of its self-defence capability, the BR.20 was fitted with a Breda model H nose turret, armed with a single 7.7 mm (.303 in) Breda-SAFAT machine gun. It was initially fitted with a Breda DR dorsal turret which was furnished with either one or two 7.7 mm (.303 in) machine guns; this turret was unusual because it was semi-retractable: the gunner's view was from a small cupola, and in case of danger, the turret would then be extended. This was later replaced by a Fiat-built M.I turret armed with a 12.7 mm (.5 in) Breda machine gun, then by a Caproni-Lanciani Delta turret mounting a 12.7 mm (.5 in) Scotti machine gun (although this proved to be unreliable). It was finally by a more streamlined Breda R turret, armed with a 12.7 mm (.5 in) Breda; this was a superior system that did not need any retraction mechanism because of the lower drag. In addition to this, the bomber was fitted with a 7.7 mm (.303 in) machine gun within a ventral clamshell hatch that could be opened when required. The original defensive armament weighed 220 kg (480 lb). The offensive payload of the BR.20 was carried entirely in the bomb bay, which was isolated from the rest of the aircraft by an aluminium sheet. It could contain various armaments in the following possible combinations: 2 × 800 kg (1,760 lb) bombs as maximum load, 2 × 500 kg (1,100 lb), 4 × 250 kg (550 lb), 4 × 160 kg (350 lb), 12 × 100 kg (220 lb), 12 × 50 kg (110 lb), 12 × 20 kg (40 lb), or 12 × 15 kg (30 lb) bombs. Combinations of different types were also possible, including 1 × 800 kg (1,760 lb) and 6 × 100 kg (220 lb), 1 × 800 kg (1,760 lb) and 6 × 15 or 20 kg (30 or 40 lb), or 2 × 250 kg (550 lb) and 6 × 50 or 100 kg (110 or 220 lb) bombs. The BR.20 could also carry four dispensers, armed with up to 720 × 1 or 2 kg (2 or 4 lb) HE or incendiary bomblets. All the bombs were loaded and released horizontally, improving the accuracy of the launch. There was no torpedo armament adopted during its service life. Structure The BR.20 had a relatively robust main structure which featured mixed-construction; the slab-sided