@voltronic I have a different approach which is to use whatever set I have to hand and wrap a rag around the object. $.02 Good luck, curious to see what you find.
@voltronic hex ftw. Hose fittings can get really sticky too, for which I don't have a good answer and a lot of bad ones (e.g. cut them off)
@b4cks4w
That's what I've been doing with rubber jar grippers, and it's been frustrating me that I can't get a secure grip. The mating fittings are easy because they are hex so I just use a crescent wrench.