Increased Oil Capacity: This cover has an increased oil capacity over stock for better performance over a longer duration. Built-in Internal/External Fins: Built-in internal and external fins transfer heat from the oil to the outside air for maximum cooling. Magnetic Plugs: This cover incorporates a magnetic drain and deep reach fill plug to capture loose particles for maximum protection. Calibration Plug: A calibration plug is set to the factory oil level to prevent overfilling. Oil Level Sight Glass: Included oil level sight glass allows quick and easy oil inspection. Fitment Note: This item fits trucks equipped with Super 8.8 rear axles. Emissions Disclaimer: This product does not require a CARB EO#. When it comes to engineering for power, performance, protection and value, aFe POWER is the only choice. Pro Series Rear Differential Cover Black w/ Machined Fins Ford F-150 15-23 (Super 8.8-12) Ford F-150 15-23 (Super 8.8-12)