Constructed entirely from stainless steel for the ultimate in durability & performance. This silencer has been designed and extensively developed to give a beautifully rich tonal quality worthy of carrying the acclaimed 'Royal Enfield Thump' we all know & love. The GMA silencer has been completely developed alongside the motorcycle, ensuring engine performance and running conditions are maintained. This has enabled us to develop this silencer to be fully compliant for both noise and emissions norms (For both BS3 and BS4 versions of the Classic 350-500). The perfect combination of materials and development has reduced the overall weight by 40% when compared to the original silencer