 As a result of increasing tank losses to shaped charge weapons, another type of panel that could enter production in only a few weeks was designed.This new type of panel used -inch mild steel instead of armour steel, and had a two-inch plate of 21ST aluminium alloy backing the face plate for reinforcement.One set of this armour was completed and tested just after the end of World War II and was considered quite satisfactory, although less so than the panels made of armour steel.