There are two points that struck me to mention first.~ 1. The obvious ~ But in this case more critical then usual.Be sure to always attach the polarity connection correctly, red to red & black to black.General instruction: (pg 3) 'Incorrect battery polarity will damage the inverter & void the warranty.Do not open the inverter, there are no user serviceable parts inside.This inverter has 'reverse polarity protection'  by means of an internal fuse, but the instructions state:(pg 7 #2) 'Reverse polarity connection will blow the fuse in the inverter & can permanently damage the inverter.Damage caused by reverse polarity will void the warranty'~ 2. All WAGAN Corporation products must be registered within 30 days of purchase to activate the warranty.Replacement products will be in warranty for the balance of the original 2 year warranty.This is an nice inverter, with more available wattage then our family would commonly need on a road trip.But this is also handy to run our desktop computer (approx 300 watts) and a lamp (approx 100 watts)for a while during a power outage.It will provide a suggested 140 watts plugged in the cigarette lighter, (Not to exceed 150 watts)That amount will power a medium size LCD -T.V. (approx 70 watts) ~ OR a laptop computer (approx 90 watts)plus other items at the same time up to 140 watts.The inverter has a USB power port compatible with iPad & tablet, for charging mobile electronics,but this kit doesn't include the USB cable that would be needed.For additional wattage over 140 up to the 400 watts this inverter will provide,it needs to be connected to the automobile/boat/RV battery (neutral to ground bond for marine applications)~ 1. Included are two cables ~ a 42" cigarette lighter/accessory adapter & 31" long battery cable clips.There is adequate holding of the ring connectors on the threaded terminals of 3 1/4 turns when onlyone set of cables at a time are connected.~ 2. The inverter runs up to 90% efficiency which supports longer running time & greater care of the battery.~ 3. Inverter has Two AC outlets which provide up to 3.3 amps.~ 4. One USB port which powers up to 5 volts at 2.1 Amps.~ 5. Short circuit protection is by means of automatic shut down.~ 6. Overload, overheat and low battery protection ~ automatic shut down.~ 7. If shut down is preceded by a buzzing sound it's possible there's excessive load or a low battery or cable problem.~ 8. All inverters will automatically shut off when the battery discharges to 9.5 volts.This lower remaining amount of battery voltage will still start the vehicle.~ 9. For T.V. and audio equipment the inverter is shielded to minimize signal interference,but it may effect T.V. picture anyway.Wagan offers suggestions what to do, among others ~ move the T.V. away from the inverter by running an extension cordbetween the inverter and T.V.~ 10. To help reduce the noise caused by power conversion when using radio frequency devices ~connect an insulated copper wire to the ground terminal ~ and the other end should be connectedto a proper grounding point.Some examples are listed. The harmonic distortion is 3% which is rather high.A start-up load is approximately twice the continuous load which is why this inverter has a peak of 800 watts.Wagan suggests to determine if an item will operate with this inverter, do a test run."This inverter will automatically shut down in the event of an output overload, so there's no danger of damagingeither the inverter or the equipment." A red LED light signals a fault.BUT ~ DON'T exceed 800 watts which will blow a fuse.To do the math ~ multiply the amps listed on the item times 120 (120V AC) to finds the wattsAll Wagan Tech inverters feature True-rated Power(tm). Which means power is tested and rated at a periodof 24 hours continuous usage under full load.Wagan says the competition claims "continuous", when in fact, they are often only 30 minutes "continuous".Afterwords, the competition's output wattage will drop down as much as 30% of the claimed wattage