Restek 0.22 um ptfe syringe filter for metals-Voa Vial Sterile Syringe Filters PES 25 mm Diameter 0.22 um Pore Size Individually Packaged 0/pk by Biomed Scientific 4.6 out of 5 stars 63 $2.99 $ 2 . 99 ($.30/Item) Get Price Millex® Syringe Filter Units, Sterile, 33mm - Sterile Syringe