1、HIGH TEMPERATURE RESISTANT, EASY TO STORE: The induction coil kit is made of 3.0mm brass wire core, can be heated to 1200℃. Includes 8 of the most commonly used prefabricated diameter coils and 2 free coils, and comes with a storage tool box that you can take with you when you're out working, while keeping your work clean and organized 2、KIT CONTAINS: 10 Coils contains 2 dia 0.79in(20mm), 2 dia 0.98in(25mm), 2 dia 1.18in (30mm), 1 dia 1.38in(35mm), 1 dia 1.57in(40mm), 2 length 29.53in(750mm) free coils. A variety of coil models and sizes can be adapted to work in a variety of ways to make your work flow smoother 3、DURABLE AND FLEXIBLE: Each coil is resistant to overheating and premature wear and is durable enough to be used at least hundreds of times. These induction coils are flexible and can be bent for a variety of purposes, you simply bend them until you achieve your expectations 4、INSULATION AND HIGH EFFICIENCY: These coils are insulated to protect you and are coated with a wear resistant coating, requiring the use of new coils if the insulation is damaged. It is electroplated to avoid oxidation and ensure contact, thus providing maximum efficiency 5、WIDE APPLICATION: Induction heater coil is mainly used for heating nuts and rusty screws to loosen them, can also be used for automobile, machinery, heat treatment of a variety of small metal parts such as gear, pulley, bearing