Magnolian High Efficiency DC/DC Converter 12V Step Down to 9V 2A 18W Power Supply Module,Waterproof

This is an excellent little 12 VDC to 9 VDC converter and works exactly as it's advertised. I am using it for camping and instead of buying lots of D-cell batteries I use this to power my 9 volt camping fan and light which normally requires 6 D-cell batteries. I can now use this little converter to run off my rechargeable AGM 12V batteries which last much longer on a charge plus power my many 12v needs during the day. I checked the 9v output of this converter and it was 9.19 volts with no load and 9.09 volts with a 0.55 amp draw. The MFR claims 96% efficiency and I believe that is quite accurate. After running this converter for an extended period of time under load it remained very cool. It's about the size of a small box of Diamond matches, so takes up very little space. It has ears on both ends for permanent mounting, and it appears to be well sealed in case of moisture. Use connectors that prevent the possibility of getting the polarities backwards, and you should be in good shape for years to come.

Does its job as requested. I connected this to a cigarette / aux plug on one end, and the other to a barrell connector to plug into a Motorola Talkabout charger. The goal was to keep two radios charged in their base station. Goal completed.Delivers 9v as promised and plenty of length on the wire leads to do what I wanted.

I purchased the Magnolian 12V to 9V DC converter so I can run a 9V Sony AM/FM/CD boom box radio in my travel trailer, running off the trailer’s 12V battery bank when we dry camp instead of depending on 6 C batteries. I soldered a 12 volt dash cigarette lighter male plug to the “line in” wires and the “line out” 9V wires to the battery connections in the boom box. This way, I can run the radio on DC or use the AC plug included with the Sony to power my radio whenever we have a full hookup. So easy, even a caveman could do it! I’m very pleased with how this set-up works in my trailer. A perfect solution to the problem of C batteries running dead all the time. Of course the trailer’s 12 V battery bank recharges every time we move to our next campsite.

After reading some of the other reviews, I was concerned about the wiring correctness.My module, like the picture, shows black as negative and red as positive. I verified this by connecting a battery on the input terminals, and checked the output terminals via voltmeter. Again, the output is marked correctly where red is positive and yellow is negative.I can only assume that this product undergoes manual assembly; therefore, some batches may have been wired incorrectly [as reported by other buyers].I have not used the module in a real application (yet) to comment on its performance; however, it seems to work as intended.

A lot of people forget that when the power goes out due to storms - whether windy, wet or frozen - that means NO telephones, Internet service or TV. Cellphones can be used for just a while until the batteries are dead. Ouch.This type of products can be hooked to a standby compact 12DC source OR even to a car battery and provide voltages to run those devices. Many Access Points, modems, gateways, routers, cordless telephones AND dead cellphones can be fed by the 3, 5, 6, 9VDC modules to keep them going. Many of the apartment/kitchen-sized televisions can be connected DIRECTLY to a standby battery.While many of the Internet devices and cellphones don't need a lot of power -- and only for short periods -- the larger 'personal TV's' DO require more power at 12VDC, so the use of them should be on an 'need basis only.'If you are confused about what you need, take a few minutes and write done the information on the devices that list voltage and amperage. Contact a Ham Radio Operator in your area (along with a bag of cookies) and he/she will be glad to offer the plans you need to provide those 'needed services' when your home is dark.Anyone that can build something with LEGO blocks, etc. or hook up a stereo system, can certainly make this happen with just a few suggestions. Unless your hands are wet OR you are wearing jewelry, you are NOT going to be shocked! This could even be a great rainy day project before it turns storm-y.Yes, you may wish to use them in your boat, car, RV, truck, cabin-in-the-woods, etc.The size is very compact, price is very right (cheaper and more powerful than a plug-in car adapter w/cord, and fast shipping make these outstanding buys.

Very Good Componentes shipment,work well. acurate

Does what it is designed but I marked it down for the same reasons other reviewers did. The sticker on the front is does not properly label the positive and negative. Multimeter read about 9.3 volts, so if you need this for something sensitive, beware.

Functions as expected, was well packaged.