Assembled Product Length: 1.5" Fastener Drive Type: HEX Finish: GALVANIZED Fastener Diameter (Imperial): 0.25" Fastener Length (Imperial): 1.5" . Strong-Drive (SDS) screw is a structural wood screw ideal for various connector installations as well as wood-to-wood applications • 4-CUT point enables easy driving with no pre-drilling and minimal spliting • Double-barrier coating provides corrosion resistance equivalent to hot-dip galvanization • Suitable for both interior and exterior applications • Head is stamped with the Simpson Strong-Tie 'no-equal' symbol and fastener length for easy identification after installation • A low-speed 1/2" drill with a 3/8" hex driver is the recommended tool for installation