The PIAT in single player appears in the Monte Cassino campaign. It takes 2 rockets to take out a Panzer tank. The PIAT in multiplayer is available for the British soldiers and it replaces the M1 Bazooka. The PIAT's rocket has a slightly lower range than the Bazooka's but it reloads faster. Like the Bazooka it cannot be used while moving and it only can be used once the player stands still.
The PIAT as it Medal of Honor: Allied Assault: Breakthrough.