We try and offer the best when it comes to what we make. We treat each new set of anvils like a "custom" set. So when you order anvils, you will need to specify your bolt pattern, your bolt size, whether you want chrome or our high nickel alloyed steel (if you don't know about that, go to the performance part section of this site), and you'll need to tell us how thick the anvils are. It sounds like a pain at first, but since this is the standard, it gives you the opportunity to make changes where they otherwise wouldn't exist; it gives YOU the power.