Synchronized operation, which sucks in waste coolant and supplies new coolant at exchange operation. Intake safety valve attached, automatically releases pressure while it is too high. `Engine Off` operation, back flush procedure to remove coolant and particulates efficiently on a hot or cold vehicle. Simple controls and quick coupler connection system make operation extremely fast, clean and easy. Simply connect to upper radiator hose with universal step adaptors. `Air Evacuation` operation to purge trapped air from cooling system to eliminate the possibility of engine damage due to overheating