DynoMax® Ultra Flo? Welded performance stainless steel mufflers feature 100-percent welded construction for lifelong durability. The unrestricted, straight-through design dyno proven to flow up to 2, 000 SCFM and support up to 2, 000 horsepower. Each muffler uses our exclusive Continuous Roving Fiberglass (CRF) Technology to absorb unwanted interior resonance while maintaining a deep performance tone. The "Pure Unadulterated POWER" of DynoMax® Ultra Flo? Welded mufflers are backed by a Limited Lifetime Warranty and exclusive 90-Day Performance & Sound Guarantee. Stainless steel construction for lifelong protection. 100-percent Welded design for maximum durability. Dyno proven to flow up to 2, 000 SCFM and support up to 2, 000 horsepower. Straight-through design ensures unrestricted exhaust flow and reduces back pressure. CRF Technology absorbs unwanted interior resonance while maintaining a deep performance tone.Pit Stop USA offers Dynomax Ultra Flo™ Muffler - 6" Round x 16" - 21" Overall Length - 4" Inlet, 4" Outlet 17225 at low everyday prices. Be sure to check out all of our products from DynoMax Performance Exhaust including DynoMax Performance Exhaust Ultra-Flow.