Expansion Chamber Seal kit for 2-Stroke 65 - 105 cc Euro Dirtbikes KTM, GasGas, & Husqvarna Motorcycles. Kit replaces old factory parts with fresh springs, o-ring seals, and pipe to silencer coupler. Kit configured to re-seal stock or aftermarket pipe with proper new swivel hook pipe springs, "O" Rings, and Hi-temp silencer to pipe coupler. 54605057000 & 47205057000 Replaces factory equipment with exact fit quality parts. Kit comes complete with what you see. Designed to fit 65cc KTM 65/85 SX &';02+ & 105SX &';04-&';11, Husqvarna TC65 &';17+ & TC85 &';14+, and GASGAS MC65/85cc &';21+ Complete set, nothing else needed to seal up your two stroke exhaust pipe.