The Gauge Doesn't Fit Anything In The UK.

@RunTheJulz Yes that's what I was thinking, I have asked if anyone knows anything about these gauges maybe someone will know something.

There's a few words in French written inside the strap maybe it's for Main-land Europe - Utiliser Ce Bouchon Lorsque La Bouteille N'est Pas En Service.

@senghenydd That statement in French just means to use on the gas bottle while not in service. I found a stick on the side gauge that is basically a thermometer which changes colour at the level of LPG in the tank.
Another way based on the same idea that the LPG under pressure is colder than the gas above, is to use warm water spilled down the side of the bottle and feel for the temperature change. Most accurate would be to weigh the bottle on bathroom scales and compare with a fully charged bottle of same capacity eg 27kg for a typical BBQ gas bottle holding 9kg of LPG

@Maturebate Yes there are stick on pads that change colour I have one it's for Butane I tried it on my Propane bottle it doesn't seem to be to work.

Ideally if someone knows how I can get this useful gauge to work using UK fittings please contact me.

I have a micro camper my bottle is very small the weight from full to empty isn't a great, deal a gauge would of been ideal.

@TheOneyouwerewarnedabout It's advertised as a gauge for gas bottles in Motorhomes etc however it's obviously not suitable in main land Britain.