The German heavy tank Tiger I was one of the most famous tanks in WWII. The Tiger had the 88mm KwK 36 L/56 main gun which could knock out a Sherman at ranges of over 2km as well as 100m thick armor at the front and 80mm on the both sides. With 1,354 models produced by August 1944, the Tiger went through many variations. The characteristics of early production Tigers included gun port on the side of turret and front fender composed of a skidproof-board. In addition, there were "Feifel" air pre-cleaners for desert use, the storage box behind the turret and fenders on both hull sides. The distinctive feature of Tiger I tanks serving in sPzAbt 501 (501 heavy tank battalion) was the exhaust cover with the heat dissipation slit.