Superior GRK Caliburn Concrete Screw - 19/64" x 3-1/2" - Each

The Caliburn concrete screws are professionally engineered fasteners for concrete and similar applications. The aggressive thread pattern creates a track that burrows into concrete and is designed for trapping excessive concrete dust keeping the threads sharp. Patented thread design, easily installed with a star drive drill bit sold separately (Pre-drill 3/16" hole with concrete drill bit, not supplied).