Refrigerant R-134a for Automotive Systems only Comes with Self-Sealing Valve. Can be used in an automotive air-conditioning system that uses R-134a. If you are using the older piercing-style recharge hoses or can tap valve with these self-sealing R-134a cans then use an adaptor.

SuperTech R-134a Refrigerant 12 oz.

Use only Self-sealing Can Tap or Self-Sealing valve recharge hose.
Do not Mix with R12 or any other refrigerant or air.
Can be used in a automotive air conditioning system that uses R-134a
Always wear gloves and safety goggles while using.
Do not overcharge the system
Follow the instructions provided on the can.