PEEK or FEP.
NanoTight™ Fittings and Sleeves are designed to connect 70 µm to 1 mm Ext. Ø capillary tubing to any standard 10 to 32 coned port normally intended for 1/16 in Ext. Ø tubing. Additionally, NanoTight Fittings can be used to connect any 1/16" O.D. tubing -- the ETFE ferrule material used in the NanoTight product line is softer than PEEK™ materials making these fittings a good candidate for connecting thin-walled semi-rigid tubing such as FEP and ETFE into 10 to 32 ports with minimal constricting the inner diameter.
NanoTight™ Tubing Sleeves connect capillary tubing into most typical 10 to 32 coned receiving ports, withhold pressures 4000 psi (275 bar), and are manufactured using FEP fluoropolymer – a highly inert, melt-processed polymer that serves as an excellent alternative to PTFE. A wide assortment of sleeves is available, ensuring the availability of a NanoTight sleeve for most applications. Many of the sleeves feature a light color tint that can help more easily identify the inner diameter for future orders. Maximum recommended continuous operating temperature of 50 °C.