Polypropylene housing. Diameters: 25 and 50mm diameters handle volumes ranging from 0.5 to 100mL. 50mm diameter PTFE syringe filter is ideal for protecting vacuum lines and pumps. PTFE resin (PTFE): For working with gases or aggressive organic solvents. 0.2μm filter for very fine particulate removal and 0.45μm pore size for most clarification applications.