The other day I removed my .177 Gauntlet from the gun safe and noticed the air gauge was at zero "0". I attempted to air it up only to hear that wonderful sound of air rapidly escaping from somewhere. Long story short....... I found that the air gauge was leaking. I removed it, took off what was left of the factory installed sealing tape, installed new sealant tape and screwed the gauge back in. I filled it to 3000 psi and it appears to be holding air just fine now. But here's my question..... when I removed the gauge there was no 0-ring under the gauge, it had been installed with just the sealing tape. Is there supposed to be an 0-ring under the gauge? Thanks. Jeff