To allow and to prevent? These two functions are what vehicle grilles are made for. Billet grilles are a custom product that can be used to cover or totally replace the existing factory-installed grille insert. Billet grilles are usually made from aluminum, stainless steel or ABS plastic. They are cut into their desired shape from a solid piece of raw material (as opposed to cast accessories that are molded into shape rather than cut). This makes billet grills a lot sturdier than their cast or forged counterparts. There are two types of billet grilles available in the market today: the bolt over billet grilles and the replacement billet grilles. For additional assistance in finding just the right product, please call 7-days a week 1-877-216-5446.