Polyetheretherketone (PEEK) tubing has become a popular replacement for stainless steel tubing in various places in the HPLC system. It is especially useful when contact between the sample and metal components must be avoided, such as when working with metal complexing agents or certain biochemical compounds. PEEK tubing also offers other advantages: it is flexible, easy to cut, has excellent mechanical stability and chemical compatibility, and can be used to 100 C. Tetrahydrofuran (THF), dimethyl sulfoxide (DMSO), methylene chloride, and concentrated nitric and sulfuric acids should not be used with PEEK tubing. Our 1/16 in. PEEK tubing is color coded for easy identification of the internal diameter. 10 ft./3 m length.