I mistakenly bought a pack of 5 brupacks 16g cartridges "for use with the beer king dispensing tap" thinking I could use them with my little mobile corny charger. They look almost identical but I realised that actually the beer king ones are about 2 mm longer, and they don't work with the corny charger, it starts to slip its thread as you try to screw it on, I think the puncture bit may be thicker too. If these are of any use to anyone they are going for a bottle of your finest.