30W multi voltage universal power adapter would meet your 90% power need for 3-12V household and office electronics, like portable bluetooth, wireless receivers, electrical toys, classic radio,battery chargers, Christmas light decoration, games consoles, kids 4 wheeler, GPS, DVR, massage gun, webcam, speaker, CCTV camera, speaker, lan phones, USB Hubs, laptop cooler, external speaker, 5V 12V LED strips Lights and more. Variable Power Supply: Input: AC 100~240V, 50/60Hz; Output: DC 3~12V Adjustable, Max 2A 30W. The variable voltage is easy to select. You can easily switch to different voltages by turning the built-in button with the provided key, such as 3V 4V 4.5V 5V 6V 9V 12V 2A 1.5A 1A 1000mA 800mA. One adapter for multiple device. Universal ac adapter equipped with a reverse polarity converter. Our DC plug polarity: inner positive(+), outer negative(-). When your power interface is opposite polarity, such as piano keyboard, guitar multi effects pedal.you can use this revers