PRO-Fit Quick Connect push-to-connect refrigerant fittings quickly connect copper and aluminum linesets for mini-split and unitary HVAC units. With no flaring or brazing involved, refrigerant lines can be securely and safely connected by PRO-Fit Quick Connect in various environments. The unique, leak-proof double O-rings sealing design creates a permanent high pressure gas seal that prevents connection leaks caused by galling, vibration, pulsation and extreme temperature changes.