Db Building Fasteners, Incorporated. In 1997 and in 2005 Moved to its Present 20,000 Square Foot Warehouse in Ontario, California. Db Specializes in Domestic and Imported Self Drilling Fasteners and Structural A325 and Tc Bolts for the Metal Building Industry. We carry Self Drilling Fasteners from Elco, Itw Buildex Teks, and our Own Vs Import Self Drilling Fasteners. Db now Produces Closure in House at our Ontario California Warehouse. Db now Stamps Closure in House with two Up to Date Stamping, Metalwork, Fasteners ...