First off, I never intended to use just one of these panels to charge my 12V lead acid car battery with the included PWM charge controller and attached wiring harness. Rather, I intend to buy multiple examples of these panels and configure them with a more comprehensive MPPT controller, LiFePO4 battery and inverter in a carry-in-car and set-up-quickly portable application. The 23.1" (541mm) square footprint is ideal for the portability I need and the price is certainly right. Fortunately, the fit and finish of the panel itself is very good. This sort of thing would have easily cost twice as much just a few short years ago. There are a few rough edges on the corners of the aluminum framing, but that's a minor point. The individual cells look to be very cleanly assembled, topped with a nice piece of glass and the caulking sealant job along the interior of the frame is very clean. I knew from the tugapower.net listing, however, that the panel would come with a 6' long piece of spindly zip cord terminated with a 2-pin trailer connector. The good news is that the junction box termination on the back of the panel is of the conventional type with a water-proof seal. It's going to be relatively easy to solder in better cabling with standard MC-4 connectors. As it turns out, the attached cable (basically 14 gauge red/black lamp cord) had a short . . . zero voltage and amp readings on the multimeter at the connector end! Readings off the tabs inside the junction box (easy to pry off the back cover with a flat blade screwdriver) indicates, though, that the panel outputs 23.6V and 2.5A on my quickly-assembled back yard test rig (picture attached.) That's very good. I tested at Noon with reasonably perpendicular panel/Sun angling on a cloudless day. Ambient temperature was approximately 70° F / 21° C Next, I trimmed/stripped the 14 gauge wires to within about 1 foot of the junction box and got similarly good readings. Subsequently, I found out that the short was in the remaining (now detached) ~5 feet of cable somewhere along the black/negative wire. I did not test the included PWM charge controller. If it was just for the panel itself, I'd give the Solperk SK-M50W a solid 5 stars. I'm knocking it down to 4 stars because the wiring harness is terrible and, in my case, non-functioning out of the box. I will be buying more of these panels for my above-described application, knowing that the other included bits will be going into the waste can and I'll need to solder in suitable 10 gauge wires at the junction box end, terminated at the other end with real MC-4 connectors. The additional attached photo here shows the back of the panel (junction box cover removed) with labeling. In case the resolution of the photo isn't good enough to clearly see, the specifications shown on the label are as follows . . . Solperk Model: SK-M50W solar panel Maximum Power (Pmax) 50W Maximum Power Voltage (Vmp) 18V Maximum Power Current (Imp) 2.78A Open Circuit Voltage (Voc) 21.6V Short Circuit Current (Isc) 3.06A Maximum System Voltage 600VDC Nominal Operating Cell Temp. (NOCT) 45+/-2°C Power Tolerance +/-5% Application Class Class A Weight 7.2lbs Dimensions 21.3 x 21.3 x 1 inch All technical data at Standard Test Condition (STC). STC Irradiance 1000W/m2. Cell Temperature 25°C. Air Mass AM=1.5