TEFIC disposable syringe filters have varies types. 1. Mainly have two series. One is hydrophilic, another is hydrophobic series. 2.Filter diameter have 13mm and 25mm two types. Filtration membrane aperture has 0.22, 0.45um. 3.Membrane material has:RC, Nylon, PVDF, PTFE,etc. Choose proper membrane is very important.