This drill bit is the new HSS steel Large Step Cone Drill Bit Set Titanium Hole Cutter, which is made from high quality HSS steel, and with titanium coated to reduce friction and heat. It is very suitable to use for drilling holes in a variety of materials, including steel, brass, wood, plastic, etc. Made from M42 high speed steel with a titanium coating to reduce friction and heat. No pilot holes or pre-drilling required. Automatically deburrs holes as you drill. Best for thin metals, steel, aluminum, copper, brass, fiberglass, PVC, etc. Product Description Unique step design This drill bit can be used to open holes of different sizes, i.e. the equivalent of a drill bit box. which are designed to accurately drill holes of different sizes, from 4 mm to 32 mm in diameter, with optimum speed and accuracy. Easily identify the size you need thanks to the contrasting sizes, laser-etched, inside the flute of the bit. HSS and Titanium Coated Our tagged drill bits are made of super strong HSS steel and coated with titanium to make them even more durable. - High speed steel tools are suitable for most general applications, offering a combination of hardness and toughness for wear resistance. - It also proves the drill's ability and durability to last through multiple drillings on surfaces such as: plastic, aluminum, copper, stainless steel, wood, etc. - Stable, working without pre-work. NOTE: When using these drill bits, the material temperature will be very high, please add water or coolant to avoid smoke. Suitable for workpieces with a hardness of 25 or less and a thickness less than 5mm for wood, plastic and thin metal.The speed of tagged drill bits is advised to be 250-400 RPM/Min.Always wear eye protection when working with tools.Length:5 Drill Bit Countersink: 4-12mm Length: Approx. 6.7cm/ 2.64"9 Drill Bit Countersink: 4-20mm Length: Approx. 7.4cm/ 2.91"15 Drill Bit Countersink: 4-32mm Length: Approx. 10.2cm/ 4.02"The 3 - between the following dimensions:Size 1: 4-12mm (4mm, 6mm, 8mm, 10mm, 2mm);Size 2: 4-20mm (4mm, 6mm, 8mm, 10mm, 12mm, 14mm, 16mm, 18mm, 20mm, 14mm, 16mm, 18mm, 20mm);Size 3: 4-32mm (4mm, 6mm, 8mm, 10mm, 12mm, 14mm, 16mm, 18mm, 20mm, 22mm, 24mm, 26mm, 28mm, 30mm, 32mm).Product Content:1*Set of 3 Pcs Step Drill Bit with 1*Storage Bag,"