PTFE Syringe Filters, 0.45 um, 25mm, Luer-Lok/Luer Slip, Nonsterile, 100 per pack, SF14469. Regular Price: $103.48. Price $93.59. As low as: $84.23. Description. Description. Constructed of a pigment-free polypropylene housing with a prefiltration stack of Whatman GMF 15 (graded density) and GF/F glass microfiber media.