A disclaimer: I am not new to canning. Been water bath canning over 30 years and pressure canning almost 10 years. I put up well over 500 jars each year. Yesterday I made up some pasta sauce and instead of water bath canning it this year, I decided to pressure can it. Everything is going fine. I took the jars out of the canner and placed them on the counter. Since I was using Tattler lids, I need to tighten the band. First one was okay. The lid of the 2nd one exploded. Nope, not the jar itself, the band, lid & gasket blew off (spewing hot pasta sauce mostly on my left hand and arm). After I rinsed my arm in cold water and soaked in cold aloe vera juice most of the night, I found the band, lid & gasket (on the floor in front of the cabinet where it blew out). I can see no damage to any of the parts. No nicks on the top of the jar. I'm not sure what happened with this bad boy. Perhaps something got lodged between the gasket during processing so that when I tightened the band, the pressue was released (in a BIG HURRY)!? I'm very aware when I'm seating the lids to make sure the rims are clean, that the gasket & lid are seated correctly and that the band is on just finger tight. Any ideas?? My arm this morning. Amazingly, it doesn't hurt at all To add insult to injury, only the jar that I tightened after canning sealed. This morning I water bathed the remaining 5 quarts of pasta sauce as well as 8 pints of stewed tomatoes & 2 pints of tomato sauce. Just took them out of the canner and tightened them all down. Off to prep & process more plums!