Adjustable Precision Scale: The hardened steel body has marked graduations on the beam, the hole diameter can be adjusted to the distance from the cutter to the center. Hex Shank Spiral Cutter strong: prevents slipping during operation Advantage: the opening is neat, the blade is strong, the chip removal is smoothreplaceable cutter and a pilot drill Application: excellent for making smooth cuts through most materials, including wood, composite, sheet metal and more. Cut plywood, hardwood, laminate, composite panels, plasterboard, plastic, Maximum depth of cut: 12cm rubber, many other materials. Adjustable Circular Hole Saw Wood Drill Bit [30-120mm] Place the two cutting blades on the blade holders firmly and correctly as shown in the adjacent figure. To adjust the size, place the inner edges of the blade holders against the size scale. Place 2 blade holders to the desired graduation on the measuring bar by screwing the hex nuts tightly with an L-shaped hex key. Use the chisel bit to drill thin wood and use the bit when the wood is thick. Before drilling, hold both sides of the wood veneer firmly, advancing the twist drill bit or chisel bit to the center of the desired hole. When using the electric drill, be sure to touch the cutting blades gradually and slowly to the object to be rough contact of the blades on the annoying object can give r a shock to your hands. The cutter body is fully heat-treated and has a good performance of high concentricity and strong torque resistance. The blade is made of high-quality carbide, which has the features of clean cutting, stable rotation and light operation. This hole opener is suitable for drilling: drilling operations on plastic wood plasterboard plywood and other materials, widely used in DIY speaker opening, projector, woodworking, plastic panel opening, etc. It is a new tool in the decoration industry, suitable for bench drills The drill can also be used on various hand-held electric drills to complete the hand-drilling (no electric drill is needed, but it is more laborious) Specification: Material: alloy steel The color is black The specific size is shown in the pictureAs Due to different measurement methods, there may be an error of 1-3mm. Quantity: one piece