AC/DC Adapter: AC Input: 100-240V 50/60Hz, DC Output: 3-12V. Advanced safety technology with full protection against overvoltage/overcurrent/short circuit/overheating. Multiple Voltage: DC Output: 3V-12V, maximum output current is 5A, just rotate the screw knob to adjust the voltage you need. Widely Used - This 60W power adapter covers 95% of home AC/DC devices, as well as 3V to 12V home electronic devices, tablet PC, scales, router, speaker, LED strip, CCTV camera system, USB charger, etc. Constant Polarity: DC plugs are positive (+) inside and negative (-) outside, which means they have positive polarity. The cards are designed to be non-reversible, so users won't confuse them. Note: A music device requires internal negatives and external positives (completely opposite). Please check carefully before purchasing. Type: AC/DC power supply Modulation method: Pulse width modulation (PWM) type Input voltage: 100- 240 (V) Output power: 60 (W) Output voltage: 3-12 (V) Working efficiency: