why do you need it? As an adapter for DIY cleaning the fuel injector nozzle, removed the injector from the engine, it can be cleaned separately. When the injector is clogged, you can use it to save expensive nozzles,This DIY Injector Cleaner adaptor kit is easily to clean most car motorcycle fuel injectors.Universal fit any 12 - 24V car, motorcycle, electric car, ATV, Boat and so on. What to Do: The electrical port of the Injector connect the 12V power by this cable. When the current is switched on, the solenoid valve in the nozzle is opened. Meanwhile cleaning liquid flush through white tube by liquid pressure in CARB cleaner bottles, then through injector to clean it. It needs the combination of 12V DC power supply and aerosol of Injector or carburetor cleaner ( not included ). Please prepare these necessary tools Package Includes: 1 x Oil Spray Nozzle Connecting Line(Large Size) 1 x Oil Spray Nozzle Connecting Line(Small Size) 1 x Cleaning Head(Large Size) 1x Cleaning Head(Small Size) Please note: there are 2 types of tube will be sent randomly.