This tool is for torx socket screws manufactured with an internal pin. They are a popular security drive for high torque applications. Quickly and easily installed and removed using matching tooling. We have a full range of AB Self Tapping and Metric Machine Screws stocked in A2 Stainless Steel and also stock Barrel Nuts and Self Drilling Screws with the 6-Lobe Pin Drive. This item is sold in singles.This is not a stock item therefore please allow 3-5 working days for dispatch. As this is not kept as a stock item, this is non-returnable. No.6 (CSK) & No.8 (BUT) Torx Pin Security Drill Bit 50mm Length - A2 ST ST