30W Reverse Polarity Universal AC Adapter Multi Voltage DC Power Supply, with 9pcs Adaptor Tips, Compatible with 3V to 12V Household Electronics, 2Amp Output

This is designed and intended for use as a power supply and not a recharger. It is designed for use with a variety of electronic devices whose power needs fit within the 3-12V at 2.5A range (or lower current levels) and where it can replace or be a permanent alternative to disposable or rechargeable batteries.The "SoulBay 30W Reverse Polarity Universal AC Adapter Multi Voltage DC Power Supply, with 9pcs Adaptor Tips, Compatible with 3V to 12V Household Electronics, 2Amp Output" supplies voltages mostly stepped at 1.5v intervals in well-marked and positively engaged steps when set by the enclosed key - a medium flat blade screwdriver will work equally well. It is unusual in that it has a means to reverse the polarity of the output voltage such that the numerous devices with a positive centre core connector are readily accommodated but, by reversing the tip, allows the relative few with a negative core to also be served.Some reviews appear to suggest that it is potentially dangerous to use, not to the user but to devices, because there is no certainty about tip orientation. That is INCORRECT and MISLEADING! The output lead is clearly labelled on its 'normal' side and provides a positive core when a tip is properly connected. Each tip is also very obviously labelled on both larger surfaces, one showing the core as positive, the other negative. It could not be much clearer unless in flashing red neon!In addition to subsequently purchasing one for personal use, one identical was first purchased by a family member as a power source for a single device, the alternative being an OEM PSU at more than twice the price as it requires a negative core supply and they are almost impossible to find as third-party alternatives! It was set up to meet its specific voltage and polarity needs and works perfectly.The tips are a very tight fit and need to be firmly connected until fully engaged - they will not easily accidentally disconnect - it needs a strong grip! The voltage dial, once set, will stay as-is and cannot easily disengage without the aid of the key or a screwdriver.Safety considerations are better implemented than with a similar product from another brand where its tips use an easily disconnected co-axial method and voltage adjustment is by a large knob whose position could be easily altered by a careless touch, passing pet or young child and pass unnoticed, risking the device should the voltage supply be beyond its limits - it does have a small LED display for output voltage but that cannot prevent an accidental voltage increase, only show that it occurred.

It works a treat.. Covers all my needs in this one stop power source.. Highly recommended..Fast delivery..

Works well, the only thing that would improve it would be to be able to change the power settings without the special key provided. Like a slider selection switch. That would have made it 5 stars.

dose what it says on the box, good quality

Packaged well. Nothing missing. Worked perfectly for a 12v ctr neg device that I needed to use. I would say that the polarity is a little ambiguous compared to others I've used.

My old switch mode psu, decided to call it a day, so I decided to go for a psu where the end connector of the PSU cable allows a polarity reversal to be made. I have two retro radios where the inner DC pins are negative polarity, so the two PSU l got do give you this polarity reversal option , and also allows you to set dc voltage output via switch on the PSU. A word of warning. Please see the diagram on the seller's Amazon site before connecting the PSU to any equipment. Most equipment with low DC voltage input do not tolerate a polarity reversal. Check your product manual for DC power rating. I have given 5 stars as the PSU are working.

Easy to use.

This power supply is ideal to power the koto royal dart scorer purchased from amazon.this scorer is powered with a DC 5v negative centre pin adator which this power supply is capable of doing and works well.