... Sewing 3.Plastic Ring or Steel Ring 4.Size, 7"x17" PP/PE needle Felt Filter Bags were ... they were used in liquid purified with filter bag vesse together. 7"x17" PP/PE needle Felt Filter Bags1).Nominal ... ) 4).High flux filter bag.(#1,#2,#3, ) 5).Oil absorbed filter bag.(#1,#2,#3, ) 6 ... ).High efficiency filter bag.(#1,#2,#3, ) 7).Activated carbon filter bag.(#1,#2,#3, ) 8). ...