ATD Tools 5664 Oxygen Sensor Wrench Flex head offers essential clearance for removal or installation of oxygen sensors when it is positioned upward and inward to the floorboard or when leverage is needed around an exhaust pipe Designed for all oxygen sensors with 7/8" hex Works on: Ford Contours, 4.6L and 5.4L Ford modular engines, 7/8" and 22mm knock sensors used on mid-sized trucks, SUVs and vans