IDEX Flangeless FlushNut Fittings are designed to include both a nut and ferrule for yIDEX convenience. Flangeless fitting are dependable, easy to use and easy to replace. FlushNuts offers the answer for those tight-space applications where nut heads often interfere with each other. It has a 1/4-28 Flat-Bottom port configuration and is for 1/8 OD Tubing. IDEX Fitting System comes with P-300 ferrule.