Minisart® SRP25 syringe filters. Minisart ® SRP with chemically inert hydrophobic PTFE is suitable for venting as well as harsh solvents with a pH of 1 - 14. Type 17575 with a pore size of 0.2 µm can be used for sample preparation and sterile filtration. It has a male luer slip outlet. Version K is a non-sterile pack of 50.