The Armor Plate end caps were the biggest innovation made after the invention of the tooling. If you have the original MDRS tooling that used pad slicks and Velcro, and have not yet returned them for upgrade, you are really missing out. The end plates are made of high carbon tool steel and are first heat treated to a specific Rockwell hardness and then sent to a company called Tech Metal, where they apply a finish called Armor Plating. These processes make the end plates impervious to cracking, splitting, chipping, and denting. They should hold up to a lifetime of hard use.