Armada 17 - Tanks BT Part 3 - the third book about tanks of the BT series is devoted to the last car of this type - wheel-tracked tank BT-7 . This tank became the crown of the development of the BT series, the most powerful and perfect machine. The nose part of the body was re-designed, a course machine gun was added to the ball mount. The main task is to strengthen weapons by installing a 76.2 mm gun. However, the main change was the replacement of the engine - instead of the discontinued M-5, a new M-17T engine was installed, which was a specially created tank modification of the M-17 aircraft. On serial machines, the armament was the same as on the BT-5 - 45 mm gun in a cylindrical tower. 76,2mm gun KT-28 was installed on a limited series of 133 BT-7A (artillery) Since September 1937, the tanks were produced with a new turret of tapered type, which had the best armor resistance. The book also provides a description and diagrams of experienced tanks - BT-SV-2 with enhanced armor, commander's KBT-7, BT-7 with a long-barreled 76.2mm L-11 gun, flamethrower HBT-7. At the end of the knig is given a summary table of TTX tanks of the BT series - from the first Christie's car to the latest modifications of the BT-7.