THE 3M™ 500 SERIES LIQUID FILTER BAGS HAS BEEN DEVELOPED WITH 3M PURIFICATION`S BYPASS AND TRANSPORT LAYER DESIGN, MAXIMIZING THE AMOUNT OF SURFACE AREA IN EACH BAG. THE RESULT IS A FILTER DESIGNED TO IMPROVE PERFORMANCE AND REDUCE OPERATING COSTS OVER STANDARD BAG FILTERS. THE 3M FILTER CONTAINS UP TO 38 SQUARE FEET OF USABLE FILTER MEDIA.