Cost effective and is fast becoming the ONLY solution for contractors and builders Does not damage floors and Great for both on-site construction and manufactured homes. Requires no special tools and Pulls the sub-floor tight back against the joist. For use with any thickness of sub-flooring and on most sub-floors and floorboards supported by joist up to 2 x 10's. Simple easy installation and The screw is made of carbon steel, solid and corrosion-resistant.