Partisil was one of the first commercial available type A silica packings on the HPLC market. The benefit of these packings compared to others was the good batch to batch reproducibility of those stationary phases. It is an irregular shaped support. Several different bonding types are existing. There are three different C18 packings available. Whereas Partisil ODS is a low density monomeric C18 phase with no endcapping, the Partisil ODS(2) is polymeric bonded and Partisil ODS(3) has an additional endcapping combined with a polymeric bonding. The Partisil PAC phase is an alkyl bonded phases with a mixed Amino/Cyano endcapping.