This is a stainless steel exhaust for the 79cc Predator. The muffler is a slip on and secures to the header using springs. The muffler is 2" in diameter. Drawing a straight line back along the side cover, the muffler will extend out 8" from that line. The muffler extends 10" behind the valve cover. (See pics). There is interference between the header flange and one of the cooling fins on the head. Either the flange and the cooling fin needs to be clearanced. Made in China.