Motion Pro Cooling System Tester Type A - 15.75mm-20mmPressurize motorcycle or ATV cooling system to check for leaks Tests radiator and radiator cap for leak and correct pressure release limit Use with a common hand pump to pressurize a non running system (pump not included) Unique design allows you to test the cooling system on a running engine to check for leaks or excessive pressure when system is hot Remote, accurate, easy to read gauge makes readings and diagnosis easy Unique radiator adapter will