The Panzer II was designed before the experience of the Spanish Civil War of 1936-39 showed that shell-proof armor was required for tanks to survive on a modern battlefield. Prior to that, armor was designed to stop machinegun fire and High Explosive shell fragments.The Panzer II A, B, and C had 14 mm of slightly sloped homogenous steel armor on the sides, front, and back, with 10 mm of armor on the top and bottom. Many IIC were given increased armor in the front. Starting with the D model, the front armor was increased to 30 mm. The Model F had 35 mm front armour and 20 mm side armor.
