The OTC Cooling System Refilling Gun, No. 6976, incorporates deep vacuum technology to remove airlocks when refilling the cooling system, eliminating the need for system bleeding and interchanging hoses. With universal attachment onto most radiator and header tanks, the tool allows technicians to pull air out of the coolant system easily while new coolant is added without spills or waste. The integrated vacuum gauge automatically tests for leaks, while the rubber cones suit both passenger and commercial vehicles with no adapter needed.