Built-in pure copper coil, the voltage transformer, more safe and durable in order to achieve high efficiency and without waveform distortion. Adjustable AC power supply: This is a brand new variable transformer. Adjustable output voltage from 0 to 300V AC. Compact and High Precision - Featuring a clear voltage output indicator/LCD display and precise metal pressure gauge, the variable transformer is designed with high precision and compact for easy transport. Safety protection: with high precision, reliability and perfect limit current protection, thermal protection, voltage overload protection, short circuit protection. An earthing port designed on the device for much more stable and secure protections. 1 power plug is available. Wide application: widely used for motor speed control, label printing machine, laboratories, railway switching tests, power supplies, satellites, equipment, telecommunication equipment, etc. 1KVA LCD Display AC Voltage Variable Transformer Rate Output Capacity: 1KWA Phase number: 1 Output voltage: 0-300V (adjustable). Nominal output current: 4A <60 °C Dielectric strength: 1500V/min Frequency: >90% Insulation resistance: >5MΩ 2KVA LCD Display Red AC Variable Voltage Transformer Output Capacity Rate: 2KWA Phase number: 1 Output voltage: 0-300V (adjustable). Rated output current: 8A <60 °C Dielectric strength: 1500V/min Frequency: >90% Insulation resistance: >5MΩ 3KVA LCD Display AC Voltage Variable Transformer Output Capacity Rate: 3KWA Phase number: 1 Output voltage: 0-300V (adjustable). Nominal output current: 10A <60 °C Dielectric strength: 500VA Meter-Red AC Voltage Variable Transformer Rate Output Capacity: 500WA Phase number: 1 Output voltage: 0-300V (adjustable). Power plug: 1