SMAKN&reg; 4 USB Car Charger Power Supply Step Down Module DC 18-40V to 5V 5a Output: 5V, within input range(18V-40V). Current: 5A (long-term stable working), max current: 8A. Efficiency: 94%.Size: 4.8 x 3.8 x 2.2cm. Core components: kim-055L packaging, tps40057 chip. With high frequency low resistance electrolytic capacitors, withstanding high voltage, high stability.