This unique patented design easily snaps on and off the A/C systems service ports under any pressure. The E-Z Snap automatically adjusts to various service port dimensions, allowing fast and immediate access into the A/C system . The swivel feature enables the user the flexibility to easily access all service ports even in the tightest quarters. Meets SAE, UL, and EPA recommendations for containment of refrigerant Our fastest and easiest R-134A couplers quickly snap on to the service port. Designed for professional A/C service technicians..