Designed for maximum torque and power across torque curve, Features a durable 16 gauge steel body with a lightweight aluminum rear end cap, Includes U.S.F.S. approved, removable screen-type spark arrestor; replacement spark arrestor sold separately, Bolts on to stock headpipe in minutes, Repackable muffler body, Optional Quiet Core Inserts available separately, Made in the U.S.A.