The Sturmtiger based on the Tiger I was armed with a short-barreled 38cm Raketenwerfer 61 L/5.4, breech-loading rocket launcher/mortar. The RW 61 launcher fired short-range (4,600 to 6,000meters). Sturmtigers equipped three Panzer Sturm-Mörser-Kompanie (PzStuMrKp)-1000, 1001 and 1002 that served mainly on the Western Front. Only 18 Sturmtigers were produced, and they did not have any effect on the out-come of the war. In their limited use, Sturmtigers proved to be excellent defensive weapons but were slow and mechanically unreliable.