This item is great for quick testing for leaks in the cooling system. Did not get a chance to try the vacuum filling portion of this kit. The caps fit vehicles well and the pump is easy to use, however, the quick disconnect fittings tend to leak when held at common angles that would occur during use. I ultimately returned this because I would like to be able to do a pressure test for more than just 5-10 minutes before the air leaks out the quick disconnect. A quick soap bubble test verified the leak was at the quick disconnect versus within the cooling system.