I have an inquire that ask for fittings for high pressure, when I ask a supplier he said that he only have Double Ferrule, so I want to know is all Compression fittings must be double ferrule ?
depends on what for, suggest calling a plumbing shop or a place like Lowes & ask the plumbing dept. Also a commercial A/C company who services C02 & ammonia units and tell them what you need to do.
