Robinair 18341 High/Low Side Automatic Coupler Set for Automotive R-134a A/C Systems Designed to connect Robinair Enviro-Guard hoses to service ports on automotive R-134a A/C systems Quick-connect design includes an integral safety sleeve which protects against injury and refrigerant loss if the coupler is disconnected under pressure Compact design easily fits into tight quarters The 6-ball coupler design provides a more stable grip on the fitting than lesser 4-ball designs Set includes 1ea. low-side and high-side automatic couplers