For several years, I have successfully used a Truma LevelControl gas monitoring unit. For those who haven’t come across them, the LevelControl attaches magnetically to the underside of the cylinder, measures the contents in the bottle and then transmits the data to your phone via Bluetooth. The device fits within the bottom rim of the bottle and is suitable for all sizes of steel containers.
Unfortunately, while the LevelControl has worked perfectly, the same can’t be said for this particular operator! Although Truma supplies a magnetic warning label, which you attach to the side of
