Deep recess to prevent 'cam-out', giving a precise and positive drive control on every screw Ribs under head for improved countersinking and to give a smooth and flush finish, also prevents splitting and material damage Coated with a high-molecular polymer lubricant that reduces the insertion torque by up to 52% and increases rust protection up to 20 times longer than a standard zinc plating Dual angle thread gives an ultimate performance and an exceptionally high pull-out resistance Patented twin cut technology for rapid "pick-up" and reduces timber splitting, Weight: 1.6314207388 pounds, Manufacturer: TIMco