Features:These soldering iron heating elements are made of ceramic materials, two line heating mode, stable quality, superior performance.High quality heating cores are resistant to corrosion , oxidation acid, alkali, high temperature, and have long service life.Optimal performance, fast heating, high heating efficiency, fast heat conduction.Good insulation, anti-static, no electric leak, no flame, in order to ensure safety.Small size, light weight, 10 pieces in this set that suitable for internal heatsoldering irons.Specifications:Type: Internal heatMaterial: Ceramic Length: 8.3cm/3.26inDiameter: 0.4cm/0.15inInput Voltage: 220V(50Hz)Power: 20WResistance: >100MQuantity: 10pcsPackage Includes:10 x Heating ElementsNote:Please allow small size error due to manual measurement. Thanks for your understanding.