I was initially skeptical because I had a hard time zeroing the gauge reliably, but once I realized that I could put a blow gun on the end of the hose attached to the gauge cluster, and evacuate the air - I was able to nail down the calibration and zero the gauge reliably. I wanted to mention this trick because it might help someone else. I am grateful that I was able to buy this somewhat specialized tool for such a fair price. I am a guy who works on engines in my garage, and I'm very glad I don't have to spend hundreds of dollars on tools like this. I won't use it very often, but when you need it you need it, and it does the job. I am also grateful that it comes with the case. The case is sturdy and everything fits well. The compression gauge I bought (a few years ago) didn't come with a case and it's a pain to protect the gauge in storage and keep the adaptors organized.
I was initially skeptical because I had a hard time zeroing the gauge reliably, but once I realized that I could put a blow gun on the end of the hose attached to the gauge cluster, and evacuate the air - I was able to nail down the calibration and zero the gauge reliably. I wanted to mention this trick because it might help someone else. I am grateful that I was able to buy this somewhat specialized tool for such a fair price. I am a guy who works on engines in my garage, and I'm very glad I don't have to spend hundreds of dollars on tools like this. I won't use it very often, but when you need it you need it, and it does the job. I am also grateful that it comes with the case. The case is sturdy and everything fits well. The compression gauge I bought (a few years ago) didn't come with a case and it's a pain to protect the gauge in storage and keep the adaptors organized.