How does this gauge work (propane tank)?

[woodchucker]

There's no connection to the tank, it's just snapped around the valve, but there's no ingress into the valve or tank?
Not the greatest pics. Just not understanding how a valve that doesn't have a pressure tap would work.

 

[mmcmdl]

I have quite a few tanks but have never seen this . Something new ?

 

[higgite]

Amazon.com

Magnets. Click on the video.

Tom

 

[WobblyHand]

Interesting use of a moving magnet to actuate the meter. This way there is no need for another hole, or o-ring or other seal, all potential leak points. Pretty clever.

 

[woodchucker]

Amazon.com

Magnets. Click on the video.

Tom

excellent thank you.. I was confused by it. So simple..

 

[RJSakowski]

Slick! A few decades ago, we used a flow meter that used magnetic coupling so the fluid was completely isolated from thew outside world..

 

[rwm]

Wow. So clever.