Polyester Filter Bag 1. Ideal medium for liquid filtration 2. Ideal material gas ... occurring due to needle holes.Type Pocket Filter Usage Liquid Filter Certificate ISO Liquid filter bag 1. (micron): 1, 5, ... ES-1, ES-2, ES-3, ES-4 Liquid filter bag Filter bag filter ability(micron): 1, 5, 10, 25, 50, ... 75, 100, 150, 200 International standard filter bag parameter: ES-1, ES-2, ES-3, ES- ...