The Flowmaster Super 44 Off-Road muffler delivers a rich deep tone with its optimum internal flow. Their sound control engineering meets all the critical Flowmaster requirements as their most aggressive, highest performing four-inch case off-road muffler. They are built in Flowmaster's standard-shaped 4'' x 9.75'' x 12'' long case, and incorporates superior strength 14-guage end caps to deal with the toughest rock crawling and off-road racing applications. Sold individually.