Features SPECIFICATIONS: Including 4pcs induction coils, 20mm, 25mm, 30mm, and 750mm free type coil, various models and sizes to meet more work needs. BRASS CORE WIRE: These induction coils are composed of brass wires with a 3.0mm brass core, and can be heated to a high temperature of 1200℃. GOOD FLEXIBILITY: These induction heater coils are flexible and durable, can be bent to any angle, wear and heat resistance, has strong practicality. HIGH EFFICIENCY: These induction heater coils are insulated and plated to avoid oxidation, ensure good contact, provide maximum work efficiency. APPLICATIONS: Mainly used for heating nuts and rusty screws to loosen them, suitable for car and mechanical repair, and for heat treatment of gear, pulley, and bearing. Specification: Item Type: Induction Heater Coil Kit Product Material: Brass Brass Core: 3.0mm Specification: 20mm, 25mm, 30mm, 750mm Free Type Application: Used to remove rusty bolts and nuts Package List:4 x Coils 1 x Storage Box Package List 4 x Coils 1 x Storage Box