23.2 mm exhaust pipe gasket for GY6 139QMB 50cc, 125cc, and 150cc engines Fits most scooters, ATVs, and buggies with Chinese built GY6 139QMB 50cc, 125cc, and 150cc engines Description 23.2 mm exhaust pipe gasket for GY6 139QMB 50cc, 125cc, and 150cc engines. Fits most scooters, ATVs, and buggies with Chinese built GY6 139QMB 50cc, 125cc, and 150cc engines. Please check the dimensions on the Specs tab to see if this is the correct exhaust pipe gasket for your 50cc GY6 139QMB engine. WARNING California Residents : Proposition 65 Warning Specifications Inner Diameter: 23.23 mm Outer Diameter: 32.43 mm Thickness: 3.63 mm