The 70 Series Big Block II Muffler uses a longer case for increased volume and added sound reduction that will still fit many applications that our wider 50 Series Big Block muffler won’t fit. It utilizes Flowmaster’s patented Delta Flow Technology for maximum efficiency and minimum interior resonance. The 70 Series mufflers are perfect for high performance street cars, most trucks, SUV’s, RVs and tow vehicles that require quiet operation with improved sound. Constructed of 16-gauge aluminized steel and fully MIG-welded for maximum durability. 5" Thick x 10" Wide x 22" Long with inlet/outlet sizes from 2.25" up to 3".