This Upchurch Scientific Super Flangeless Nut is excellent for those connections that need to be broken frequently and tubing assemblies because they swage onto the tubing. We manufactured this nut from PPS (polyphenylene sulfide) which offers high tensil strength and excellent chemical resistance. It has a 1/4-28 Flat-Bottom port configuration and is for 1/16″ or 1/32″ OD Tubing.