Low pressure main air gauge Works great, no problems, reading 1 PSI. inches of my digital pressure gauge. Separate air-down parts that release air slowly is kind of a joke. Some of them work, some of them don't work. They're everywhere if they check the PSI after a stop. It's also not very good actually holding the lock nut in place. This device is worth buying for the gauge but the rest of the kit is not. If you are looking for other items in this set, look elsewhere.