The Cllena Dual USB Socket Charger has been working great so far for an off-grid battery system I built. The customization options for exchanging out hubs is really nice and I'm currently running 2 usb and 1 12v plug. This does work with either a 12v or 24v DC system. Wiring was slightly confusing and I would only really recommend this to someone who at least has some basic electrical experience. The price point at $30 at the time of purchase is a little steep but the convenience of it was overall worth it. 4/5

I got this to provide a power outlet for my RV's 12vdc crock pot, which draws 8 amps continuous for a few hours at a time while we're driving. That's a significant continuous duty load so I installed it using the right gauge primary wire to match my application, used the provided crimp connectors and then fused the circuit directly at the power source. It does a fine and safe job. Nice plus is the volt meter and USB ports. I rotated my bezels 90 degrees and removed the flip cover from the USB ports, so it's now vertically positioned on a cabinet wall near the counter. Works great, looks great. Hey, soup's up!

Just installed yesterday and am very pleased. I installed in an RV and is so handy. Lets you view your battery voltage and allows cellphone, tablet and any thing using a USB port for power. Has LED light in the on/off switch, so that you can tell if the panel is powered up, There are no wiring instructions, however the polarity for each unit is clearly marked and the spade contacts are silver and gold. Slide on insulated terminals (6) are provided and mounting screws are provided (4). You can wire this in multiple configurations to fit you needs. I wired so that the 12VDC to the on/off switch is in series and all the other units are in parallel to the on/off switch. Thanks!

Here's how to wire this if you want the switch to turn off (and on) all the items in the plate. Incoming negative from fuse block (or battery) to the brass terminal on the switch, then on to the negatives of each device. It's one cascading flow from blade to blade. For the switch, the brass is negative, and the other two are positive. Device terminals are labeled with "+" and "-". Connect the center terminal of the switch to the positive terminals of the devices. The positive line coming from the fuse block (or battery, with an inline fuse) goes to the remaining terminal of the switch (outboard, silver in color).

This cascading effect requires doubling up wires with the push connectors -- SEE PHOTOS. After a lot of time messing around, I decided to use push connectors that are one size too large (yellow in color). This allowed me to put two wires into one connector and get a good connection when I crimped, and then the connector was a little loose when I pushed it onto the blade (of the devices and switch). I crimped the connector with a pliers to give it a tighter fight, and this solved the problem. I looked for connectors that fit these blades perfectly while allowing multiple wires, and couldn't find them anywhere -- Home Depot, hardware stores, and automotive stores. I was, of course, able to use the correct push connectors (blue) for those blades that only had one wire.

About fuses. You must use them, or risk a fire. I'm using a 10-amp fuse for this application, and so far it's working well. However, since I'm using two dual usb charging ports, with a maximum of 2.1 amps per port (2.1 x 4 = 8.4 amps), plus a little extra for the voltmeter and LED lighting, the fuse could blow with even a small spike. If this happens, I'll go up to a 15 amp fuse. Look, I don't know much about electricity other than simple automotive / marine DC wiring, and even then I'm lacking. IF MY THINKING IS INCORRECT, SOMEBODY LET ME KNOW. Thanks.

I purchased this item to use on an ammo can emergency battery box. This unit contains a mounting plate, power switch, volt meter, Dual 2.1 amp USB port, a cigarette lighter port and crimp terminals. It is easily installed and works very well. I'm very happy with this item, and it is less than half the price of comparable units sold by other vendors over the internet. I plan on purchasing more of these for upcoming projects.