Features 1,Made of quality material, which is durable and for long time use. 2,When it operate in the air, no crackling sound, but the temperature is very high, can easily ignite paper, plastic, even very fine wire. 3,For middle school science experiments, electronic instruments, negative ion generator, science and small production. 4,The transformer primary has two windings, one main winding and one feedback winding. 5,​The two thick and fine coiled copper wires are the positive poles, which are respectively the main winding tail and the feedback winding head, connected to the positive poles of the power supply.​ Specification Features: Made of quality material, which is durable and for long time use. When it operate in the air, no crackling sound, but the temperature is very high, can easily ignite paper, plastic, even very fine wire. For middle school science experiments, electronic instruments, negative ion generator, science and small production. The transformer primary has two windings, one main winding and one feedback winding. The two thick and fine coiled copper wires are the positive poles, which are respectively the main winding tail and the feedback winding head, connected to the positive poles of the power supply. Specification: Current: ≤2A Input Current: ≤0.4A Size: Approx. 25 x 20 x 15mm/1 x 0.8 x 0.6in Package List: Note: Package List Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.