3D printed with FDM system. Features and components: - 2.1x5.5mm Female Jack Connector (Charger included 12V 1A); -Switch / turn inverter. You can reverse polarity without having to modify the connections; -High quality copper terminals; -Base adapted for 4x4 cars .; -Anti-vibration pad at the rear to absorb possible vibrations from cars; LCD screen with a multitude of functions: -On-off button .; -Input voltage up to 30V .; -Adjustable output voltage of 0.5-30V (precise and fast adjustment in different selectable scales 0.01V-0.10V-1V); -Efficient heat sink; -Protection against overvoltages and short circuit; Easy visualization of the parameters of Input / Output Voltage (V), Output Intensity (A), Output Power (W) and Ampere Hour (Ah) .; -Use time counter. All test benches are delivered tested and calibrated for correct operation from the first moment.