Sharp teeth resist loads and increase cutting speed - cutting speed and finish depend on material thickness and teeth per inch. The thicker the object being cut, the thinner the blade should be - Size 1, 2 and 3 blades are recommended for sawing metal - Sizes 4, 5, 6 and 7 are good for sawing wood - Size 8 can be used for sawing plastics. Forged from carbon steel - Finish machined - High hardness and strength - Hardened to stay sharper longer. Easily replace damaged or worn saw blades. These blades saw all around with 360 degree cutting capability - arc sawing is easy and the blade won't jam - great for wood cutting and shaping, jewelry making, metalworking, crafting and more. To install the saw blade, insert the saw blade into the small hole on the round end of the saw blade holder. The saw blades are divided into 1-8#, and the difference in thickness is not too large. The gap in the installation hole is controlled by the thumb screw and the hexagonal screw on the back at the same time., Weight: 0.0220462262 pounds, Manufacturer: eMagTech