The Tolsen 54179 is a self-drilling metal screw designed for securing metal or aluminum panels, including roofs and facades. These screws feature a Phillips cross-recessed head and a specialized drill point that allows you to fasten materials without the need for pre-drilling, which saves time during installation. Each screw measures 4.2x38mm and is finished with a zinc coating to provide better resistance against corrosion. This pack contains 500 pieces, making it a practical choice for contractors or homeowners working on larger structural projects where a consistent, secure hold is required across wide surfaces.