The main issue with both royal mail and parcelforce who both accept low powered air guns wether that technically includes gas powered or not i am not sure, is that both do not accept gas containers wether empty or full. Which means if you send them and they are checked they can decide to destroy them if they want to, i had a madbull gas grenade destroyed by royal mail who stated it didn`t matter wether it was empty they will still destroy any gas container sent.
Gases, including flammable, non-flammable, toxic and compressed gases Gases including flammable, non-flammable toxic and compressed gases, new, used and empty gas cylinders, butane, ethane, refills for lighters, fire extinguishers and scuba tanks, life jackets, nitrogen dioxide and carbon dioxide canisters (culinary foaming devices and soda stream).
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