This is an essential item to have in my truck (F150) at all times. Works great and very quick and easy to use.

I purchased the GT4000s, but ended up returning it, not because of a problem, but because Amazon lowered the price of the GT4000A to only $10 more than the GT4000s, and the GT4000A included the prewarmer tech which allows the unit to function in subzero weather by warming itself up before turning on.Both are good units, but for the slight increase in cost, the GT4000A makes more sense.

12/2024: I had to finally use it in winter and the override / boost feature is a necessity if your battery is dead. It seems good at detecting a when to start discharge when crank is initiated and not just dumping everything into a dead battery. The Avapow wouldn't consistently output since the battery voltage was too low. Gooloo FTW.Initial review: I tested it by performing 10s no fuel cranks with 15 minute cool downs. And this did 3x more starts and the engine cranked faster than a 4000A Avapow I also bought at the same time.

Don't be fooled by it's small size compared to conventional jump boxes, this has more power than many four times it weight. Quick to charge, with the convenient screen showing percentage, it's ready for multiple uses before needing recharge. Removable cables and it's light weight make it easy to transport from vehicle to vehicle and into the house for charging.

تمت تجربتها لأكثر من مرة على سيارة صديق ، كانت ممتازة واشتغلت السيارة بدون مشاكل ولم تسحب من بطارية الباور سوى ٥% في كل إشتراك وأراه معدل نزول جيد.

I've been researching these compact jumper units for about a year, and they look pretty impressive - some better than others. But the price points - Oy vey! As sales went up the cost came down, Amazon offered this unit for 150 bucks. I jumped on it (pun intended). I was hopeful, but skeptical, this little box would deliver on the promise. But so far it appears to be everything the seller claims - and more. I've only had it for about a month and have yet to use it in an emergeny situation - but it seems capable.Was a little disappointed no hard case was included. However, the factory box it came in is built like a brick s***house. For long-term storage this container will work just fine. I'll be keeping mine primarily in the door well of my truck, though. The unit with the cables was heavier than I expected, which I think is a good thing. The main case seems quite rugged and possibly waterproof as well. The display is excellent - very easy to read. A blessing for my tired old eyes. All functions are easy to access, and operation is quite intuitive. No one should have any trouble making it work. There are a couple things you need to know beforehand, so I'd suggest you [gasp!] parse the manual before going into combat. No worries - the instructions are short and sweet.My unit came 80% charged. This sounds about right for a Lithium Ion array (safety first). Tried the 5V USB port to charge it up - it worked, but it was waaay slow. Still, it's nice to have that option in a pinch. But for fast charging, the included cigarette adaptor kicks butt (again, pun intended). As the photos show, I started at 80% when I plugged it into my truck (engine off). Charge rate showed 125 Watts - wow! Higher than Gooloo advertises. Charging really took off, and within 15 minutes was up to 90%. Another 10 minutes or so and it hit 99%. Not too shabby. at 99%, things slowed down quite a bit. That last 1% took about 12 minutes.Now for the real test - starting my truck with the battery disconnected. This is not recommended, except as a last resort. Some vehicle computers can go spastic doing this, and operating a running engine with the box connected can damage your alternator. BTW, this can also happen using standard jumper cables. I know my vehicle pretty well (2012 Chevy Colorado), and have previously tested the computer's resilience by disabling the battery while running. But again, be careful. Many newer PCMs/ECMs are quite unforgiving. A word to the wise.The result: Started my cold engine (48 degrees ambient) in 2 seconds flat. Also fired up my yard tractor without the battery in 6 seconds. The tractor's V-Twin engine is notoriously hard to start, even with a fully-charged battery. I'm looking forward to trying this on bigger engines, especially diesels, but for the time being this is all the testing I could do. The no-load potential of the Gooloo measured 16.2 Volts, which seems to be typical for these boxes according to the Project Farm guy and a few others. Doubtful that this voltage level will cause any problems with your computer or alternator.Only complaint I have is a minor one, nothing I can't live with. The side input/output ports are grouped together and covered with a long, hinged rubber weathershield. Nothing wrong with that, except that when the jumper leads are plugged in the hinge stays open and all the ports are exposed to the elements. This could *potentially* allow moisture, rain, snow, beer, etc to infiltrate. Sure, in most cases this won't be an issue, but for an otherwise well-engineered product this seems kinda cheesy. Maybe the next generation will address this.There you have it. So far, I haven't unearthed a single major flaw in this device. Of course, durability can only be measured over time. Normally I wouldn't award 5 stars to something still under warranty, but I'll stick my neck out on this one. If it tanks, rest assured I'll be back to let y'all know.

Alright, so update on my previous review: This is an essential for me, especially for camping. I've had to jump my car (2014 town and country) about a dozen times since purchasing this due to a battery fault. This thing is the definition of overkill. Each jump takes somewhere between 10 and 15% of the battery life, and each jump, the van acts like it has a brand new battery, which is perfect. Biggest thing i've jumped so far is a GMC Yukon, which had zero issues.Outside of jumping cars, this is the champion of camping power. Its capable of charging all your mobile devices, rechargeable camping gear, even a laptop, without being the size of a lunchbox, and can recharge anywhere your phone can. Not to mention it can use any accessory your car's cigarette lighter can, and has a light. The only downside is this doesn't have any AC power, but that was never the point. Given the choice between this and a 150w inverter or a jackery (with a built-in inverter) and a car jumper, I'm probably going to pick this every time.What i've noticed since purchasing this:+ Perfect for camping: This can charge a phone, tablet, battery fan/light, other power packs, even a USB-C charge capable laptop without a hassle.+ Charges on a USB-C phone charger. 16w USB-C won't charge your laptop, but it will charge this, which charges your laptop.+ Jumps stuff others won't touch: When "smarter" jumpers detect a bad battery and refuse to jump, this will jump your car, without hassle.+/- Light is designed for local light or signaling, not as a flashlight. Great for keeping people from running into you, not so ideal if you need to see someone at a distance.+/- This will fast-charge phones, but is not compatible with 45w super fast charge 2 some phones are capable of.- Clamps are chunky. Not a big deal, but these do get in the way on certain vehicles where the battery is in an awkward spot.TL;DR at the top: Huge battery, extremely flexible power options (is currently charging the laptop i'm writing this on), easily starts average cars and acts as a massive power bank for whatever you want to do. Just a little bulky but well worth it!Detailed review:About two years ago, i received a NOCO GB40. Supposedly rated to 1000 amps, it time and time again failed to start the 3.6l V6 engine in my Town and Country, my roommate's Buick Rendezvous, really anything I ran across that needed a jump. After two separate incidents in a week where the GB40 failed to start cars under ideal circumstances (full charge, warm engines, no mechanical faults), it was retired, and the GT4000 put in its place.Out of the box, the GT4000 is chunky, at 9x4x2.25", its larger than your average brick. Throw in the accessory kit (jumper leads, USB-C to C and USB C to A cables, PD100 charge cable and a cigarette lighter adapter) and you'll have a fun time getting this into your glovebox. But then again, the GT4000 can probably jump much larger things than your SUV. The packaging is superb, and nothing in the box was really susceptible to shaking in the first place, but I'm fairly confident the box would have kept everything secure regardless.The User Interface is simple, there's 2 buttons, power and boost. Power turns on the device, and when held, turns on a surprisingly bright flash...light? The very bright LED strip is obscured by a milky plastic cover, so it works well as a flood light, but not so much as a long throw flashlight. You can change the mode or turn off by clicking the power button repeatedly. Once on, connect your power leads to the port on the side of the charger, plug in your battery, and click "boost" if the backlit LCD screen doesn't say "Ready". The included leads are plenty long for the majority of batteries out there. I didn't feel like waiting to drain my battery to test this, so I disconnected the battery from my Town and Country and started the 3.6l V6 directly off this. No shock, but there was no hesitation, no difference from using the standard battery, successful start. Obviously this is a bit like using a sledgehammer to hit a nail, but it works!Outside of its duties as a car jumper, the GT4000 has a plethora of charging ports. First is a USB-C, which can deliver PD100 power to charge a USB-C PD compatible laptop, or 18w fast charge for your phone. This is also how you charge your GT4000. Next to this are two USB-A ports, one feeds 5,9,or 12 volts like Samsung's rapid chargers, the other feeds 2.4a at 12v. There is also a port for a cigarette lighter port, so you can run a compact compressor or an inverter. Thanks to its 99.2wh rating, this can easily double as a power pack for camping or long-haul flights on budget carriers, as it will charge most USB-C chargeable laptops once, or run your phone for days at a time. And since it is under 100w, this pack does not have any specific regulations with the TSA outside of needing to be carried in a carry-on bag. (note, you may wish to leave the jumper cables at home if you take this on an airplane, no clue how the TSA will react. I'm not responsible for any TSA-confiscated items or enhanced screening protocols).The LCD display is extremely easy to read, and gives you a lot of data regarding your charger, including charge percent, status, charging rate (in watts, which is very useful for testing the power output of USB ports), and more. If you manage to sufficiently discharge the battery (below 20%), the display will flash, making it very clear to recharge. It sounds like this unit has an internal warmer to keep its battery at an optimal temperature for discharge, i've yet to need to use it, and will update the review once a need arises. I also cannot speak to the longevity of the device, as I haven't had time to cycle it hundreds of times, but I'll update this review as that becomes relevant.Overall, this well exceeds the needs I have for the battery, acting as a car jumper, laptop and phone charger, and USB tester. If you're looking for something you know will start your car whenever and wherever you manage to find yourself, this is it. The only negative is the size, but if you can find a spot in your car to put a couple bricks that you don't need to think about, then it shouldn't be a concern, and is well worth the extra space for the added capabilities over similar, smaller products.P.S. the jumper plug for this are the same as the Noco GP40, but reversed, so you can't use the leads interchangeably.