The ProntoSIL is the silica support of the Alliance for Chromatography. Due to the fact that it is manufactured under very stringent conditions the resulting silica has a purity of 99.999%. The optimum manufacturing process guarantees an excellent batch to batch reproducibility. The silica is available in several particle and pore sizes. Therefore a wide range of different applications, i.e. in SEC (Size Exclusion Chromatography) but also for the NP HPLC of large molecules is given.