It has 3 types of needled felts; including pure glass fiber type, compound type with blended glass fiber and synthetic fiber and synthetic type. It has three-dimensional micro porous with high porosity and low resistance. The dust separation efficiency is up to 99.9%, higher than that of woven fabric. This product is suitable for bag filters with impulse jet or high velocity reverse air clean-down technology. The compound glass fiber and synthetic fiber needled felt is made of a certain amount of synthetic fiber blended into the felt. Synthetic fiber has stronger interlocking capability. Compared with pure glass fiber needled felt, the peeling strength between felt and base fabric and friction resistance has increased 3 or 4 folds. Thus its service life is strikingly prolonged. It is mainly used for cement and carbon black industries. The synthetic fiber needled felt is made of P84 and PPS. It is mainly used for dust separation of coal-fired boiler and precious metal recovery in non-ferrous metallurgy. 208 dust collector bags 729 dust collector filter bags are made of staple polyester fiber.It has good intension,elongation and acid resisting.The dust collector bags is the ideal filtration material because of its good permeability and ifficient dust filtration.The products can be widely used for oil refining,mineral,chemical industry,environment protect,medicine field.etc.