This 25-piece Black Bronze Oxide HSS drill set is designed for superior durability and performance, offering a longer life and better heat resistance compared to standard HSS drill bits. Black Bronze Oxide Coating : Provides enhanced corrosion resistance and durability, with up to 50% longer life than standard HSS bits. Heat Treatment : Bits are heat-treated to 950 degrees Fahrenheit, reducing friction and speeding up the drilling process. Versatile Use : Ideal for drilling both hard and soft metals, including aluminium, stainless steel, mild steel, copper, brass, as well as materials like wood, MDF, PVC, polycarbonate, acrylic, ABS, nylon, and composites. Sizes : Includes drills in sizes from 1mm to 13mm in 0.5mm increments. Heat and Corrosion Resistance : Excellent performance in resisting heat and corrosion. Storage : Supplied in a sturdy plastic storage case with a barcode and euro hook hanger. Brand : PTI