RedCap Cylinder Head Studs & Exhaust Nuts are engineered to provide a secure and precise fit for GY6-B 4-stroke engines, including 170cc, 180cc, and 200cc 1P63QML EFI models. Designed for optimal compatibility, these high-performance components fit seamlessly with TaoTao Bull 200, TANK 200, and other engines featuring a 57mm stud spacing and B-Block Valve.