Astro Pneumatic Universal Air Powered Cooling System Pressure Tester 7856 DescriptionThe Astro Pneumatic Universal Air Powered Cooling System Pressure Tester 7856’s pressure regulates shop air to test any cooling system or radiator cap for leaks. Quick connector works on nearly all brands of cooling system testing caps and adapters. The Astro Pneumatic Universal Air Powered Cooling System Pressure Tester 7856 fills even large cooling system almost instantly, and provides constant pressure on leaks to trace their source. Gauge displays the common pressures levels for different cooling systems and regulator will max at 30psi to prevent damage.