The Mastro2 column has a biocompatible PEEK-lined stainless steel body with a high pressure polymer frit. This inertness eliminates adsorption and reduces tailing for compounds that tend to form chelates with metal surfaces, especially those containing phosphate groups. Maximum operating pressure: 20MPa/200 bar/3000 psi. pH: 2 - 7.5. Maximum temperature: 80C (pH 3 or higher.)