Our Fingertight Ferrule is designed specifically for use with our two-piece fittings. It is offered in both biocompatible PEEK . It has a 1/4-28 coned port configuration and is for a 1/16 Tubing OD. It is available in natural color PEEK and a natural color 10 Pack, natural color Tefzel (ETFE) and a natural color Tefzel (ETFE) 10 pack.