Expansion Chamber Seal kit for 2-Stroke 50cc 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. Replaces factory equipment with exact fit quality parts. 45105057000 Kit comes complete with what you see. Designed to fit 50cc KTM 50SX 2002 & Up, Husqvarna TC50 2017 & Up, and GASGAS MC50 2021 & Up Complete set, nothing else needed to seal up your two stroke exhaust pipe.