high-speed steel material: drill bit cutting wheel is made of high-speed steel, with an outer diameter of about 0.87/0.98/1.26/1.38/1.73/1.97 inch/22/25/32/35/44/50 mm. After many of processing, the teeth are clear, burr-free, and not easy to rust Caution: drill resin cutting wheel is made of resin, thickness is about 0.04 inch/1 mm, inner diameter is about 0.08 inch/2 mm, outer diameter is about 1.26 inch/32 mm, keep the slice perpendicular to the cutting object, and the blade connecting rod should be inserted into the bottom of the electric mill, not too hard Stable diamond material: diamond cutting wheel is made of diamond particles, with high cutting efficiency, good quality and long service time, which can meet your daily cutting or slotting of most metals, fine wood, plastics, etc Wide range of application: these tool accessories are equipped with 4 screwdrivers of 2 types and 12 mandrels, which are easy to install and replace. pay attention to safety when using color:As shown Material:Metal Package Contents: 12 x HSS blades 40 x resin cutting plates 20 x diamond cutting wheels 12 x mandrels 4 x screwdrivers Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.