The NORJIN PS30SWI is a professional analog DC power supply that can power many devices. It is a highly stable, efficient, compact, high-quality switching power supply with a fixed DC power output of 13.8V and a maximum current of 30A. Short-circuit protection and automatic current limiting ensure the safety of the operator and any connected electrical equipment. Noise Offset Design There is a Noise Off-Set control that can be adjusted to eliminate pulse noise from the power supply.This function is specially designed for communication.When there is noise, you can use the noise cancellation knob to eliminate it.Works with cellular phones, CB radios, scanners, ham radios, mobile ham radios, etc. Desktop Bench Power Supply The output voltage is continuously adjustable from 9V to 15V or set at a fixed 13.8V.The meter displays the voltage or current, which can better help to use. Cigarette Lighter Socket Design with 12V cigarette lighter socket adapter to supply power to portable device.Cigarette lighter socket on the front for plug in equipment to 10A Built-in Cooling Fan A built-in cooling fan prevents overheating and keeps the unit running under heavy loads.Suitable for mobile phones, civil radios, scanners, ham radios, etc CAUTION 1. Use the correct terminal to connect the cable even if the chassis of the equipment is negatively grounded.2. The power must be turned off when the unit is plugged into a wall outlet.3. If a short circuit occurs during output, the unit will be protected by the short circuit protection function. Please turn off the unit and repair the cause of the short circuit immediately before turning on the unit.4. Do not use the unit for equipment that requires high current input during startup, such as electrical equipment. Do not use the unit to charge car batteries.5. Make sure the product is always properly grounded to prevent electric shock and reduce noise.