Fitting needed to adapt virgin R134 Refrigerant tanks to low side service coupler. Works with an machine including Yellow Jacket, Robinair, Bosch, Mac Tools. 1/2″ Acme Female X Low Side R134A; This adapts most 30 lb virgin tanks to a low side blue service coupler fitting,so the Refrigerant can be taken in through the low side hose on the AC machine. 1/2″ Acme Female to Low Side R134A RTI Part # 023-80147-00 All names, numbers, symbols and descriptions are used for reference purposes only. It is not implied that any part listed is the product of these manufacturers.