Initially, I just purchased online, but ordered the wrong part. I called and talked to a real person, who helped me order the correct part and offered a reasonably priced return shipping label. That was a welcome change from other recent online purchase interactions.
One COmpressed air Gauge with 1/4" Male NPT Threads coming out the side of the gauge. This gauge will show up to 200 psi and there is a mark every 5 psi. The Actual gauge is about 2.2" in diamter, and about 1" Deep with the threads sticking out the side about 3/4". This is a very good quality gauge.