Material: PE, PP, Nomex, P84,PPS, Acrylic etc.  
Rings: Stainless steel ring, snap ring, needle punched felt ring
Application: With filtration precision of 99.9%, HEPA filter bag is suitable for most industrial fields. The structure feature of HEPA filter bag is that it is composed of layers in grades. Inner layer is   the thickest to provide the best pre-filtration and largest collection ability. While the middle and   outer layers are with high density and micro-fiber. It can provide a better filtration precision.   There are at most 12 layers in a HEPA filter bag in different density and precision .This can   lead a stable filtrating efficiency and dust-collection ability. It also will increase the lifetime of   filter bag (according to the total flowing ability). Moreover, HEPA filter bag owns the ability of   hydrocarbon (oil) absorption because of its special structure.HEPA Filter Bag realizes the lost   cost and high efficiency of replacement in the industrial filtration.