The internal thread is W21.8 RH compatible with Autogas adapters to travel in the world.
Bottle MUST be EMPTY if no 80% shut off valve fitted.
Refueling without non-return valve you must close the bottle valve first before disconnecting gun after refueling.
WILL NOT TAKE ANY RESPONSIBILITY FOR FILLING THESE BOTTLES
1 kg ≈ 1.96 litres lpg