Eaton uses some impressive technology in its SENTINEL filter bags, like this bag PE-200-P01H-WW-50. A 200 micron rated bag, this filter is made of polyester felt that is welded to create the shape of the bag. Welding as opposed to sewing, makes for extremely strong seams that don't have needle holes (which cause bypass). All SENTINEL felts are silicone-free and made of non-migrating media. The sealing ring is another amazing piece of technology. This ring has a sealing lip that activates with pressure. That means the seal improves as pressures increase, and it is reliable across different temperatures and micron ratings. This Eaton bag comes in box quantities of 50.