STRUCTURAL SCREW 5/16 X 6 IN GOLDRSS screws which are 3 1 8" and longer have a six threaded CEE thread that enlarges the screw hole for the non threaded portion of the fastener, allowing the wood to settle easily and increasing the screws drawing strength. The CEE thread also reduces the friction on the screw shank which can result in lowering the driving torque and the likelihood of splitting the wood. This is why the RSS screw is an efficient lag screw alternative.