Water Removing Filters and Filtering Equipment WaterGuard ® manufactures cartridge and spin-on filters , portable filter buggies and stationary filter vessels that remove emulsified water and particulate from fluids, such as hydraulic and lubricating oil, gasoline, diesel fuel, other hydrocarbon based fluids, and compressed air. WaterGuard ® products contain proprietary hydrogen bonding media with 2 to 3 times the water removing capacity of competing filters and with superior particulate removal (Specifications ). WaterGuard filters are very competitively priced and cost less to operate than other filters on the market. Some of our industrial customers have not had to change their oil in years.