The bioinert Scepter column has a PEEK-lined stainless steel body with a high pressure polymer frit for a completely metal-free flowpath. The C4-300 phase is recommended for mid- to large-sized molecules (above 5000 MW) to ensure retention and avoid size exclusion effects. It is ideal for LC and LCMS analysis of peptides, proteins, intact monoclonal antibodies and their subunits up to 150 kDa. PLS hardware eliminates adsorption and reduces tailing for compounds that tend to form chelates with metal surfaces, especially those containing phosphate groups. USP L26, pore size: 300A, pH range: 1-10, max pressure: 100 MPa/1000 bar/14,500 psi, fully endcapped. Phase is similar to Acquity Protein BEH C4, PLS hardware is unique.