SSP-G 61mm Big Bore Kit Cylinder Head for 125cc – 150cc GY6 Scooters, ATVs, and Go KartsSPECIFICATIONS: Exhaust Valve Diameter: 23mmIntake Valve Diameter: 27.75mmExhaust Port Diameter: 26.5mmIntake Port Diameter: 27.5mmCOMPATIBILITY: Amigo – 150cc Scooters, ATVsApollo – 150cc Scooters, ATVs, Go KartsBaotian – 150cc ScootersBaron – 150cc ScootersBintelli – 150cc ScootersBMS – 150cc Scooters, ATVs, Go KartsCoolster – 150cc Scooters, ATVs, Go KartsDiamo – 150cc Scooters, ATVsFlyscooter – 150cc ScootersGorilla Motor Works – 150cc ScootersIce Bear – 150cc Scooters, ATVs, Go KartsItalica – 150cc ScootersJCL – 150cc Scooters, ATVs, Go KartsJonway – 150cc ScootersKandi – 150cc Scooters, ATVs, Go KartsKinroad – 150cc Scooters, ATVs, Go KartsKMD – 150cc Scooters, ATVs, Go KartsLance – 150cc Scooters, ATVs, Go KartsLeike – 150cc ScootersLinhai – 150cc ScootersLongbo – 150cc ScootersMotobravo – 150cc Scooters, ATVs, Go KartsMotofino – 150cc ScootersMotorino – 150cc ScootersNST – 150cc Scooters, AT