Drillcrete^® Flat Head Concrete Screws with their full body shanks, offer superior holding power over other tapered shank concrete screws on the market. Our Drillcrete^® concrete fasteners aren’t just painted for looks; we use a specially formulated fluorocarbon coating that passes a 25 Kesternich cycles with less than 5% red rust (DIN 50018, 2.) They come packaged with the proper size concrete drill bit for “out of the box” convenience.