The Panzer IV gives fire support to the lighter tanks. Although its role would change as the war progressed, it was the only German tank to stay in continuous production over the course of the war. It too was relatively rare in Polandin 1939, with only one platoon in each Panzer battalion (although once again 1. Panzerdivision and Panzer Lehr had more). By the Battle of France each battalion had a full Mittlere Panzerkompanie equipped with Panzer IV tanks.