The Yato HSS Twist Drill Bit 4.0mm 10pcs with model number YT-4438 has been designed for accurate drilling of materials such as cast iron, steel, metal and plastic. It is made of top quality high-speed steel (HSS) and has a reinforced cutting edge. High-speed steel ensures a longer service life, optimum performance and accurate drilling. This drill also facilitates maximum removal of sludge from the hole.The Yato HSS Twist Drill Bit 4.0mm 10pcs has been designed for accurate drilling of materials such as cast iron, steel, metal and plastic. It is made of top quality high-speed steel (HSS) and has a reinforced cutting edge.