This is not a generic or knock off of an FSI filter bag, it is a 100% brand new authentic Filter Specialists, Inc (FSI) 50 micron polypropylene felt size #2 (7" OD top x 32" folded flat length) filter bag with patented PolyWeld welded seams and welded on patented Polyloc plastic flanged top with built in handles. MADE RIGHT HERE IN THE USA!!! This patented Polyloc top fits all size #2 bag filter housings but actually snaps into the collar plate of FSI bag filter housings to prevent bypass around the top of the filter and to prevent the filter bag from unseating in backflow conditions. FSI patented PolyWeld welded seam liquid filter bags (aka bag filters) like this one provide superior prevention of bypass (zero) compared to bypass threw sewn seams or inferior welded seams. The same can be said about the plastic flanged patented Polyloc top which is welded to the body of the filter bag. Made in the USA by Pall Filter Specialists, Inc. (aka FSI).