Rotalock suction fittings for R-134a refrigerant. The suction fitting has 7/8″-14 threads for the suction hose, and 1-14 thread for the compressor fitting. The fitting also has a low side 14mm charge port. The fitting is made of steel and uses O-rings on both connections and Teflon seals where the fittings fit onto the Compressor. This fitting is common on York Compressors. Please make sure the York you are mounting this to is not a Tube-O fitting, refer to pictures to see the difference between a Rotalock and Tube-O fitting.