Rock-On Star Flat Head Cement Board Screws provide a superior surface for tile with their patented serrated head design. Enjoy one-handed installation with Rock-On's Star drive recess and enjoy the peace of mind of Climacoat's corrosion resistant finish. Perfect for high moisture areas such as baths, showers, countertops, and floors, these ANSI A108.11 certified screws come with a T-25 Star drive bit for easy installation. Enjoy a smooth tile surface and unparalleled security today!