Racing silencers in polished stainless steel, not homologated, can be mounted ?slip-on? on the set of V7 headers (not V7 Classic, Stone, or Special) and are fixed to the standard brackets. They are developed and made in collaboration with Arrow. They grant a proper sound, weight savings and improved performance in midrange and top end power, which translates into better acceleration. They recall the look of racing silencers on V7s that competed in races for production-based bikes in the 70?s. They do not require a specific ECU mapping.