Review on FJC 6031 R-12 Side Can Tap: Convenient and Reliable Refrigerant Refilling Accessory by Jesse Wells

Great product, meets your needs. The biggest advantage is that the faucet can be used with any type of refrigerant that comes in the right size cans. This eliminates the need to deal with all the different refrigerant valves used on top of canister faucets. The only problem I see with the faucet is that I'm not sure how long the faucet can hold leftover refrigerant in the can without leaking. The seal is just an airtight seal created with a rubber gasket pressed against a hole in the side of the can. You will likely need one for each type of refrigerant you are dealing with.