Our short, PEEK, Super Flangeless Headless Nut is very easy to use and is an excellent choice for connections that need to be broken frequently and tubing assemblies because they swage onto the tubing. It eliminates the loosening of fittings due to tubing twist and holds tight during vibration. This nut has a 1/4-28 Flat-Bottom port configuration and is for 1/16 or 1/32OD Tubing.