Pretty decent quality gauge set. My only complaint is that the brass adapters have a knurled edge, rather than a hex. A hex would make it a lot easier to seat the adapter in the spark plug socket. The knurled edge means that, inevitably, you will use a set of grips to tighten the adapter to make a good tight seal, and this will shave off brass into the spark plug socket. Otherwise, this is a great kit at an excellent price.