My thoughtful man bought this get- up last week. I'm using it to seal my jars for curing.
Only good for wide mouth jars. I screwed up and was doing it wrong at first, I tried sucking the air out with the sealer ring ON. Oops! It won't work with the sealer ring on. Doh. Live & learn!
Photo below is the vacuum to suck the air out of the jar.