I used this to check the cooling system after installing a new heater core to make sure there were no leaks. It worked well.
Pros
EASY TO USE: Remove the original radiator cap, choose an available radiator cap from the test kit and install it on the radiator opening. Operate the hand pump at up to 10-15 psi (avoid pressures up to 35 psi). Check the pressure gauge reading, if the reading drops automatically, it means there may be a leak in the radiator. Please check the cooling system and repair if necessary. It usually takes about 10 minutes to test for leaks, very easy and quick to use.