Unique design allows you to test the cooling system on a running engine to check for leaks or excessive pressure when system is hot. Unique radiator adapter will work with most motorcycle, ATV and UTV applications equipped with a 30 mm spout. Use with a common hand pump to pressurize a non-running system (pump not included). Remote, accurate, easy to read gauge makes readings and diagnosis easy. Tests radiator and radiator cap for leaks and correct pressure release limit. Specified range is most common on European manufactured radiators. Designed to work on radiator necks from 20 mm to 24.5 mm. Pressurizes motorcycle cooling systems to check for leaks. Adapter also available separately..