Fastener SuperStore, Inc. Thread Forming Screw 350437

2 X 1/4 High Low TFS / Phillips / Pan Head / 18-8 Stainless Steel A thread forming screw with a double-lead, consisting of a high and low thread. The lower thread varies in height from 1/3 to 1/2 that of the higher thread, which is sharper and flatter than a standard thread. For use in plastic, nylon, wood or other low-density materials. Thread design reduces driving torques, enhances resistance to thread stripping, improves pullout strength and lessens risk of cracking the work piece.