Easy to install, the manual is not inlcuded, However, You may search some manual on tube. The only thing they need to change is one of the gasket that is included needs to be the one between carb and air filter housing. After installation, It instantly fires up, Your Powerful mowers & Equipment deserve A Perfect Carburetor Suitable for 4500 5200 5800 stroke engine 45Cc 52Cc 58Cc carburetor combinationCarburetor replaces your old OEM. To replace an existing carburetor, simply replace and ride again. Give your machine the power and torque you really deserve, and enjoy more fun with power at your fingertips. brand . 1 carburetor.