23 mm exhaust valve for 125cc GY6 QMI152/157 and 150cc GY6 QMJ152/157 go-kart & scooter engines This exhaust valve is used on a wide variety of scooters and ATV brands and models that have Chinese built 125cc GY6 QMI152/157 and 150cc GY6 QMJ152/157 enginesDescription 23 mm exhaust valve for 125cc GY6 QMI152/157 and 150cc GY6 QMJ152/157 go-kart & scooter engines. This exhaust valve is used on a wide variety of scooters and ATV brands and models that have Chinese built 125cc GY6 QMI152/157 and 150cc GY6 QMJ152/157 engines.Please check the dimensions on the Specs tab to see if this is the correct exhaust valve for your Chinese built 125cc GY6 QMI152/157 and 150cc GY6 QMJ152/157 scooter engine. ? WARNING California Residents: Proposition 65 Warning Specifications Valve Head Diameter: 23.0 mmOverall Length: 65.3 mmStem Diameter: 4.95 mm