Simpson 0.220 x 12" Strong-Drive SDWS TIMBER Screw (Interior) E-coatModel No. SDWS221200 Coating Material. E coat Electrocoating Length. 12 Head Diameter (in.) 0. 76 Shank Diameter (in.) 0. 22 Drive Type. T40 6 Lobe Head Type. Low Profile Head Thread Type. Serrated Threads Thread Length (in.) 3 Point Type. SawTooth Point Color. Black The Strong Drive SDWS Timber (Interior Grade) screw formerly, the SDWS Log screw is a structural wood screw designed for cross laminated timber assemblies, mass timber construction, log