Jiangsu Zhenya Special Screw Co.,Ltd is one of the leading China wood screws manufacturers and suppliers,Website: , as a professional company, our productive factory is able to produce CE certification wood screws at both high quality and low price. Welcome to buy discount and cheap, or wholesale products from us. Wood screws are used to fasten wood to wood or attach objects to wood and offer a pleasing, finished appearance. They pull wood pieces together as they are tightened, which can make clamping unnecessary, and can be removed more easily than nails so entire assemblies can be dismantled or fixtures dismounted with relative speed.                      A H J T M G N Phillips Size Head Diameter Height of Head Width of Slot Depth of Slot   Driver Diameter Depth Width Max. Min. Max. Min. Max. Min. Max. Min. Max. Min. Max. Min.   2 0.172 147 0.051 0.04 0.031 0.023 0.023 0.015 0.102 0.089 0.063 0.017 1 4 0.225 0.195 0.067 0.055 0.039 0.031 0.03 0.02 0.128 0.115 0.089 0.018 1 5 0.252 0.22 0.075 0.062 0.043 0.035 0.034 0.022 0.154 0.141 0.086 0.027 2 6 0.279 0.244 0.083 0.069 0.048 0.039 0.038 0.024 0.174 0.161 0.106 0.029 2 7* 0.305 0.268 0.091 0.076 0.048 0.039 0.041 0.027 0.182 0.169 0.114 0.03 2 8 0.332 0.292 0.1 0.084 0.054 0.045 0.045 0.029 0.189 0.176 0.121 0.031 2 9* 0.358 0.316 0.108 0.091 0.054 0.045 0.049 0.032 0.258 0.245 0.146 0.034 2 10 0.385 0.34 0.116 0.098 0.06 0.05 0.053 0.034 0.204 0.191 0.136 0.032 2-3* 12 0.438 0.389 0.132 0.112 0.067 0.056 0.06 0.039 0.268 0.255 0.156 0.036 3 14* 0.491 0.437 0.148 0.127 0.075 0.064 0.068 0.044 0.283 0.27 0.171 0.039 3 1/4 0.507 0.452 0.153 0.131 0.075 0.064 0.07 0.046 0.283 0.27 0.171 0.035 3 5/16 0.635 0.568 0.191 0.165 0.084 0.072 0.088 0.058 0.365 0.352 0.216 0.061 4 3/8 0.762 0.685 0.23 0.2 0.094 0.081 0.106 0.07 0.393 0.38 0.245 0.065 4 1/2 0.875 775 0.223 0.198   0.106   0.091 0.103 0.065 0.424 0.411 0.276 0.069 4 Wood Screw Sizing        • Shank Diameter is measured on the smooth portion of the screw above the threads. Working With Wood Screws - Common Sense Tips Use soap or wax to lubricate screws in hardwoods. Keep brass screw heads from twisting off. Use the same size steel screw to thread the wood, then insert the brass screw. Your screwdriver bit is less likely to slip when you use Phillips or Robertson (Square Head) style screws. Use a drill with an adjustable chuck clutch to avoid stripping screw heads. Drilling pilot holes prevents your wood from splitting, and allows for a tighter joint.