aFe Power's rear differential cover brings performance engineering to the protection of your truck's front-end. This differential cover is constructed out of durable die-cast A380 aluminum with reinforced ribs for maximum strength. This cover fits the 12 bolt-9.75" axles. Built-in External Fins: Built-in external fins transfer heat from the fluid to the outside air for maximum cooling. Magnetic Drain Plug: This system incorporates a magnetic drain plug to capture loose particles for maximum rear-end protection. Also included is a 1/8" NPT calibration plug that is set to the factory fluid level which eliminates accidental overfilling. Optional Accessories Available: This cover works great combined with a oil level sight glass (Part Number: 46-00001) or deep reach magnetic fill plug (Part Number: 46-00002). Note: This differential cover fits 97-15 Ford Trucks with the 12 bolt-9.75" differential. Modifications may be required on 2010 and earlier vehicles. When it comes to engineering for power, performance, protection and value, aFe Power is the only choice.