Feature: The product is made of high quality M42 steel, high hardness, good wear resistance and long service life. Hole saw is processed by precision electron beam welding. The welded interface is not prone to cracks and the surface is smooth. The product has been heat treated and the hardness has been greatly improved. The product is suitable for the opening of various types of materials, such as plastic, wood, aluminum, etc. Hole saw is suitable for use with bench drill and electric drill. It has precise and convenient hole opening. Specification: Material: Steel(M42) Application: Aluminum, wood, plastic Package list: 9 * Hole Saw 2 * Connect rod(A2, A4 ) 2 * Hex Wrench(Big, small) 1 * Connector Note: The actual product color may deviate from the photo due to light. There may be a slight deviation in the measurement of product. 1. When using the hole saw, please be sure to master, select, control, and tachometer and add coolant continuously to prevent the blade from cracking. For example, use high-speed gun drill, and control the switch during operation. Open and close as much as possible to reduce its speed, widely used in the drilling of various types of drills on bench drills. 2. The hole iron plate is more than 5mm, first open about 1mm deep, and then use the positioning drill to drill through the hole through the hole, which is more convenient to discharge iron filings. .