... Ring 4.Size, 7"x17" PP/PE needle Felt Filter Bags were made by PP,PE,Nylon,Nomex and Oil ... Absorbent.And they were used in liquid purified with filter bag vesse together. 7"x17" PP/PE needle Felt ... ,#2,#3, ) 2).Absolute micron filter bags.(#1,#2,#3, ) 3).Long time filter bags.(#1,#2,#3, ) 4 ... ).High flux filter bag.(#1,#2,#3, ) ...