For a time-tested, reliable, and affordable filter bag to suit your needs try the Eaton SNAP-RING. PO-10-P04O-50 is an Eaton 10 micron filter bag (size 04). Sewn into the top of the bag is a Polypropylene SNAP RING that creates a seal. Made under ISO 9001 quality standards, this bag is made of the best silicone-free materials available. This line of filter bags is available in 14 different materials, micron ratings and ring types. This bag model comes in box quantities of 50.