Ernest Sweetland and George H. Greenhalgh patented the first automotive oil filtration system in 1923. They called their invention Purolator, short for the words pure oil later, and they began a story of quality and innovation that continues to this day. Over the years, Purolator developed filtration products for transmission fluids, power steering fluids, hydraulics, coolants, crankcase emissions, and other liquids and gasses. As the holder of thousands of patents, Purolator has consistently innovated and led the very industry that they invented