Rugged Ridge 16595.13 Black Boulder Aluminum Differential Cover for Dana 30 Constructed of a356-t6 cast aluminum for strong impact resistance Matte black powder-coated texture offers a high quality finish with a stylish look Machined sealing surface allows gaskets or RTV sealant to adhere easily, providing great sealing Magnetic drain plug provides extra protection against oil particles Magnetic drain plug provides extra protection against oil particles