Initially i bought this for the "emergency" jump start and really only used the air compressor. The air compressor isn't as fast as ones at a gas station for example, but it absolutely will inflate a 19" tire from 20 psi to 36 psi in under 10 min, which will greatly save time and effort. In the winter the gas station nozzles get full of ice and snow and water gets in the lines, which you don't want to put into your tires so this is a way for you to control that from happening in a very portable way.

Now - With the covid pandemic and the lack of travel, I've found myself coming out to my vehicle with a dead battery and flat tires. In 20 min I was able to get all my tires to proper PSI levels and immediately jump start my vehicle! This has happened now multiple times and this unit has never failed to assist me. Without this unit I'd be looking at 100s of dollars in tow fees to get my vehicle out of the underground garage where it's parked. This has been a lifesaver and I highly recommend this product! It's not as portable as the pocket lithium ion battery jump starters, but i trust it far more, it drains much slower and has an air compressor in it that is highly useful.
This is an excellent product and I'm quite glad I purchased it!

Even though I just have a small compact car, I still went with the largest J88 model. Always nice to know you have plenty of power to start even the most dead engine, plenty of power to run the air compressor, and plenty of power for use as a household backup power source for an extended period of time in the event of an emergency. My unit came almost fully charged, just needed a short time to top it off. It's VERY nice that this unit comes with an AC adaptor so you can charge it using your household power outlet, in addition to the also included DC car power charger. This was my very first portable power source, so it took reading the manual to figure it out but overall it's very intuitive to a first-time owner. The only switch/dial that was a bit confusing was the black front rotary ON/OFF switch for the charging cable. I can barely read the ON/OFF points on the dial so wasn't sure how to turn it at first. The air compressor seems powerful, not sure if it would have enough sustained power and internal cooling to be able to last long enough to inflate a full set of car tires, but for the typical use of topping off a car tire from time to time it's just fine. I can't speak for the accuracy of the pressure gauge on the front. If it's typical of these portable machines, it's often inaccurate so you would do best to have a high quality pressure gauge with you. The 90-degree locking knob on the chuck for the inflator tube is plastic, which hopefully won't break easily. This unit is nicely equipped with some storage bins on each side which are large enough to hold all included power cords, air tubing, and adaptors. They aren't big enough to hold much more than that though but at least they're there. Overall, you can't ask for much more in a device of this size and price point.

Lots of features, connects to and recharges from our solar paneled roof-top car carrier, versatile.

The only negative thing I can think of about this item is that the charging is a little fussy compared to a previous item of this type that I owned (it finally died, and the POTEK replaced it). My previous device allowed me to leave it plugged in indefinitely, so it'd always be fully charged, without damaging the battery. It could not be overcharged. It had the same type of battery this item has, so the difference isn't battery chemistry, it's the technology of the devices. The POTEK has a max amount of time you are told that you can leave it plugged in. If it needs to be plugged in for at least several hours after use to charge, but can't be plugged in more than (I think it was) 20 hours, it means having to set an alarm or reminder to ensure I unplug it to avoid damage. Ideally, it'd be protected against overcharging.

THIS THING IS AWESOME.

The best: is that you can keep charging it (the manual says its good for it to be charged all the time). So I just let it charge at all times in the back of my car.

The worse: I think my light on my wrist watch is brighter than the LEDs on this thing. But meh, in an emergency situation, any light will do.

I've only owned it for a month, and already I have jump started 5 cars, 3 of which were a large truck variety (and actually it was 3 back to back jump starts, the guy kept letting it die lol).

The power inverter works well! It powered some speakers at a beach for several hours. It can power a soldering iron for doing electrical work in car. It can KINDA power a heat gun. It can NOT power a vacuum cleaner.

Also, I have owned several emergency compressors, and the number one problem is the pressure gauge. The PSI air pressure gauge on this Potek device is AMAZING!!!! Probably the best that I have ever seen. Even while it is running (a LOT of vibration) the gauge is readable. It seems accurate as well. I use it to fill up my car tires all the time. It is great!