The Simpson Strong-Tie Strong-Drive SDS Heavy-Duty Connector screw is a 1/4 in. Dia high-strength structural screw ideal for various connector installations as well as wood-to-wood and engineered wood applications. It installs with no predrilling and has been extensively tested in various applications, the SDS Strong-Drive 1/4-in. wood screw line includes stainless-steel screws in 1-1/2 in. x 3-1/2 in. L, suitable for fastening Simpson Strong-Tie stainless-steel products. Offering the same easy-driving, split-reducing installation of the standard SDS screw, these screws are made from Type 316 stainless steel, stainless-steel SDS screws are appropriate for higher-exposure environments where maximum corrosion-resistance is required.