... Steel Ring 4.Size,#1,#2,#3,# Polyester Liquid Filter Bag was made by PP,PE,Nylon,Nomex and Oil ... they were used in liquid purified with filter bag vesse together. 1).Nominal micron filter bags (#1,#2,#3, ) ... ,#3, ) 7).Activated carbon filter bag.(#1,#2,#3, ) 8).Pleated Media filter bags.(#1,#2,#3, ) ... V (End construction V style) H: SF (Silicon free) ST (Standard) Polyester Filter Bags