Footnotes

1. BT–2. Source: Russian Military Zone. The armour scheme comes from the Russian Military Zone (which has a diagram for the BT–7) with a maximum armour of 13mm instead of 20mm. Problems with the 37mm gun resulted in 350 out of 610 vehicles built being equipped with MG only. The BT–2 could run on either wheels or tracks, a change which took about 30 minutes. [up]

2. BT–5. Source: Russian Military Zone. The armour scheme comes from the Russian Military Zone (which has a diagram for the BT–7) with a maximum armour of 13mm instead of 20mm. The model 1933 was short-lived and was quickly replaced with an improved, welded, two man turret. I have assumed that this was the 1934 model. The BT–5 could run on either wheels or tracks, a change which took about 30 minutes. [up]

3. BT–7. Source: Russian Military Zone. Other sources cite a maximum armour of 22mm but I have used the armour scheme from the Russian Military Zone as it is more complete. The BT–7 could run on either wheels or tracks, a change which took about 30 minutes. [up]

4. BT–7A. Source: Russian Military Zone. The armour scheme comes from the Russian Military Zone. The BT–7A was a light artillery tank with a larger, straight sided turret, of which 154 were produced from 1936 to 1939. The BT–7A could run on either wheels or tracks, a change which took about 30 minutes. [up]

5. BT–7M. Source: Russian Military Zone. The armour scheme comes from the Russian Military Zone. The BT–7M was produced from 1939. In 1940 at least 50 were uparmoured by adding armour plate on the upper hull front and turret front and sides, but I have no information on the extra armour thicknesses. Possibly others were similarly uparmoured in 1941. The BT–7M could run on either wheels or tracks, a change which took about 30 minutes. [up]