You can get a kegland mk4 regulator with the correct fitting for mixed gas from BrewKegTap but they are sold out at the minute. I have 2 mk4's, one for CO2 and one for mixed, the only difference is the connectionKegland mark IV reg happy with a Beer gas mix. But you need someone who is putting beer gas in a normal CO2 cylinder for this. I'm not sure if beer gas comes in these normally , I think it's in a nitrogen type cylinder and that needs a different stem on the regulator or a different regulator.