Sun Through Industrial Co. Ltd. is a Taiwan-based screw manufacturer specializing in self-drilling screws. Sun Through has been developing new and innovative products to satisfy a variety of customers from all over the world. Specifically, spiral self-drilling screws are our signature patent product that has extremely excellent drilling capacity. The spiral self-drilling screws can penetrate a steel plate with a thickness of up to 30mm, and, more amazingly, save 50% working time than regular self-drilling screws. From raw steel to forming, from heat-treating to plating, all of Sun Through's products are made in Taiwan to ensure quality.