Filter membrane: Hydrophobic PTFE membrane Support & drainage layer: Polypropylene Core, cage & end fittings: Polypropylene (Optional reinforced PP end caps for sterilisation. Gaskets & O-Rings. Ethylene Propylene , FEP encapsulated, Silicone, Viton. Media grades. S = Standard grade P = Integrity test grade. Micron ratings . S Grade = 0.1, 0.2