PTFE adapter, precision made, for use when making NPT thread connectors to Ace-Threds. One end designed to make leaktight seal with Ace-Thred without use of O-Rings, other end accepts NPT male thread. Can be used when making connection at top of rapid prep columns or rigid connection between solenoid and first diluent/effluent vessel in ACE Flow Thru Bioassay Diluter System. Use 5844-78 or -85 and 7855-829 for #50 size.