Oh, if you are using threaded cartridges without a cover, be sure not to grip the cartridge with your bare fingers when you inflate the tyre. As the gas depressurizes into the tyre, the CO2 cartridge will drop temperature rapidly. I gave myself a minor case of frostbite a couple weeks ago by forgetting about this. Everything is OK, but the skin was sensitive for several days.

I bought a foam sleeve to put over my 16g cartridges from now on.