This AC/DC adapter can apply to most appliances. which the efficient voltage is from 3V to 12V.This adapter output is 3V/4.5V/5V/6V/7.5V/9V/12V. You can easily set the voltage by a little key. which included with the adapter.Equipped with 6 adapter plugs. the different size will fit for your appliances well. and solve your various problems.This 6 adapters in 1. which can largely save your space and the one can replace a lot adapters. Attention: DC Plug Polarity: inner Positive(+). outer Negative(-). Polarity is irreversible.Adjustable Variable Multi-Voltage Power Supply. Lots of Options. Meet Your Various NeedsThis is a universal power supply for all your pedals. effects. wireless receivers. printers. chess set. LED base. games consoles. paper shredder. DVD players. radios. speaker. audiotape recorders and players. electronic gizmos. blood pressure monitor. and many other 3V to 12V Small Home Electronics devices.Product Weight: 3.1 ouncesCord Length: 43.3 inches(about 110 centimeters)Adapter Input: AC 100V~240V 0.25A 50/60HzAdapter Output: 3V/4.5V/5V/6V/7.5V/9V/12VMade of high quality MosFet and PWM circuitryTIP:If the required voltage is not in the options. please choose the close voltage. For example. if you device needs 5.5V. you can choose 5V or 6V.Centra Positive(+) Power Supply. Polarity is Always the Deciding FactorDC Plug Polarity: inner Positive(+). outer Negative(-). The Polarity is not compatible ALL Devices. It is not compatible devices that require Central Negative (-) Polarity.Friendly Reminder: The Polarity is irreversible. The wrong polarity would cause some damage to your device. Please Check What Polarity You Need First. you can find your device polarity information printed beside the power port.Note: NOT compatible with laptop or other Over 12W Devices;Package Included:1 x 12W Universal ac adapter6 x DC Tips6 Adapter Tips Specifications:2.5*0.7mm; 3.0*1.1mm; 3.5*1.35mm; 4.0*1.7mm; 5.0*2.1mm; 5.5*2.5mmInstructions:1. Connect the correct adapter tip and make sure that it’s firmly attached to the dc input port of your device.2. Set the right DC output voltage. There are 7 options for you. DC 3V/4.5V/5V/6V/7.5V/9V/12V.3. Connect the adapter to the electrical receptacle.