Shim-pack Scepter columns consist of an organosilane hybrid particle for excellent stability and performance. The C18-300 phase has a larger pore size than Scepter C18-120 and is less retentive, which reduces analysis time and is more reproducible for the analysis of compounds that are strongly retained on typical C18 columns. It 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, and is compatible with 100% aqueous mobile phase conditions. USP L1, pore size: 300A, pH range: 1-12, max pressure: 45 MPa/4500 bar/6,500 psi, fully endcapped. A guard column is recommended to prolong the analytical column lifetime. Similar to XBridge Peptide BEH C18.