Indestructible! You won’t break these covers, we guarantee it. Made of 3/8“ cast steel, painted black inside and out, these heavy-duty covers are designed to protect your differential and all its working parts for as long as you own your vehicle. These indestructible covers have been “44 caliber tested” - if they can take a bullet at point blank range (don’t try this at home!), they can take all that the trail has to offer.