Ideal for Rapid Analysis. Shim-pack GISS C18 maintains the same ultra-high inertness and wider pH range as the Shim-pack GIST C18, while providing rapid separations with symmetrical peaks. The optimization of surface area, pore size and chemical bonding delivers superior peak shapes. It is ideal for LC/MS/MS analysis and enables MS-compatible buffers to be used due to extremely inert silica gel. Bonded Phase: Octadecyl Groups, Particle Size: 1.9 ?m, 3 ?m, 5 ?m, Pore Size: 20 nm, Surface Area: 200 m2/g, Carbon Loading: 9 %, End-capping Yes, pH Range: 1 to 10, USP Code: L1.