Inexpensive filtration solution for light-viscosity oils. The Xtract® Depth Filter with wound cellulose media is an inexpensive method for obtaining high-efficiency filtration in light-viscosity oils such as hydraulic, turbine or transformer oils. It helps clean (not just screen) the oil by dislodging contaminants. Ideal for removing sludge and varnish, it provides high efficiency filtration at very low micron levels (<1 micron).