A book about the history of the creation and development of a whole series of domestic wheeled tracked tanks BT, originating from the tank M. 1940 American designer J. U. Christy . The reasons for the purchase of the Kristi tank and its further development by domestic designers are described in detail . The book presents serial modifications of BT tanks, as well as various combat and support vehicles created on their basis. In addition, the most interesting projects of machines that were not embodied in metal are considered. Examples of the combat use of BT tanks in Spain, near Lake Hassan, on the Khalkhin-Gol River, in liberation campaigns in Western Belarus and Western Ukraine, during the Soviet-Finnish war in the winter of 1939-1940 are given. During the Great Patriotic War and the war with Japan. The book includes a large number of illustrations, many of which have not previously been published. The publication is designed for a wide range of readers interested in the history of the development of domestic tank building and combat use of tanks.