Schumacher DSR108 DSR ProSeries Batteryless Jump Starter - 12V, 450A for Gas and Diesel Engines

These are the best jumper you can get IMO. At least, that is to say I believe that ultra capacitor jumpers are the best. This one has no problems, and even supports a glow mode for diesel glow plugs. Not all capacitor packs do. These work differently than a battery. Capacitors can dump all of their energy very quickly, as well as charge quickly. However they do not hold it when sitting, and they do not hold very much total energy. This means it will provide extremely high energy cranking (more so than your normal starter battery!) but only for a few seconds before needing to scavenge more power. If your car cranks a while before starting, this will not be the jumper for you. If you car always starts right away, this jumper will never fail to start your car. Lithium battery jumpers hold onto their charge and have a lot more total energy, but will likely be dead when you need them if you just leave them in the car. They also wear out extremely fast and are a fire hazard under the extreme conditions of starting a car. Oh, and they flat out don't work when frozen. When you most likely need them. These capacitor jumpers on the other hand are nearly indestructible. They work perfectly even in deadly extreme conditions, and they work without fail. This device works by drawing energy from your battery and boosting the voltage to fill the capacitor bank. This takes about 2 minutes, depending on how much voltage is available in the dead battery. Upon filling completely up, it monitors for a sudden reduction in voltage and assumes you turned the key to start the car. It then dumps all of that full 13+ volts back into the car battery at high amperage, but only for a few seconds. Even on a big V8, this never failed on any vehicle I tested it on. Some newer cars, particularly Fords will not even attempt to do anything when you turn the key at low voltage. No clicking, nothing at all. In these cases you have to press the button on the capacitor pack to start a count down beeper. Quickly get into the vehicle and be ready to start it. As soon as it gives the go, crank the engine. It should start right up. In the event of a failed attempt, you need to wait for the capacitors to charge back up before trying again. If your battery is absolutely zero volt dead, think of this jumper like a cordless jumper cable! Just clip it onto any donor battery or vehicle and wait until it's full. Then bring it over to the dead car and start as above. Even if you don't have that option available, you can even charge this pack (SLOWLY) via USB C or fairly quickly with the included 12v lighter socket adapter. In general, if your dome light can even slightly glow orange, this will charge up and start your vehicle without any outside energy source. I've used one of my fleet of these over 30 times, it works as new still. It can start my turbo diesel jeep, which really takes a LOT of amps to start. My only complaint is that the admittedly nice silicone coated wire leads are a bit short. I would also sort of prefer if this used an EC5 or other connector so that the leads could be replaced or removed for storage. The weakest component of this will be the wires right where they exit the body. I will likely change this some time myself in the future.

This was the BEST $100 I have ever spent! I wasn’t even aware that a product like this existed until I stumbled across it on Amazon. Before I go any farther, if you are even thinking about getting an auxiliary jump-starter for your car, get this one—NOW! You will not regret it. So here’s my background. I drive a 2013 Buick Enclave with a 3.6L V6 with a SprawlMart battery that has been a constant disappointment in temps below 20° or if I have not started the vehicle in over a week. After several times of being late for work, I decided to look for an alternative power source. I was tired of the embarrassment of desperately begging neighbors and strangers to jumpstart me. In fact, I was searching for a new battery here on Amazon when I stumbled across this capacitor bank and thought I would give it a try. Best hundred dollars I have ever spent!!! So far, I have used it over five times in temperatures below zero and it has successfully jump-started my car every single time the first time in spite of my frozen/dead battery. The beauty of this device is that it charges itself in just a few minutes from your dead battery! So, as long as you have a working voltage of 3 Volts or more, and most dead car batteries can supply at least twice that much, it will charge the device just fine. I’ve been able to jumpstart my car in LESS than five minutes each time. Let’s see you do that with your jumper cables. And speaking of cables, the wires on the device are small and easy to use in freezing-cold conditions. So how does this work? Well, first, you need to understand that this device is not a battery. It is a bank of capacitors. If you don’t know what a capacitor is, go Google it and learn from that because I don’t have time nor space to explain that here. All you need to know is that this a solid-state device that is able to store up enough current quickly in order to start your car. And here’s the beauty of that: it NEVER wears out! It will work forever. So no need to buy a replacement in a couple of years. Now let me clarify something about my car. My 2013 Buick Enclave is a wonderful car in that it has started the first time every single time (with a good battery). So this jumpstart device works very well with it. Having said that, I have not used this device on a vehicle where you have to grind the starter a lot, so I cannot attest to how well it will perform on a vehicle that requires a lot of churning of the starter motor. So, if your vehicle is of that nature, then I would recommend getting the device that has the higher CCA capacitance. In conclusion, I could not be happier with how this jumpstarter device has performed for me. I highly recommend it, and I know you will not be disappointed. As that insurance company says, “It’s so simple, even a caveman can do it”!

First one I received did nothing when hooked up, and I wasn't connecting it to a totally flat battery, still at 11V, just needed a boost. I could see a couple of the LEDs in the voltage scale were out of place, so maybe some rough shipping, not sure. Second one, started charging when hooked up, but after, say, half a minute, a spark would pop from the black lead connected to the car frame and the unit would stop. Gave it a second try and the fault light came on. Gave it a third try and fault cleared, charging began, spark from the negative lead again, to the point that the lead actually jumped and change position slightly. A friend has also purchased one when I did. We tested hers in the same manner on her car and got the same result. Starts off as it should, then big spark from black lead. Also sent that one back. That's three, I think enough of a test to be done with this one.

Ok so I bought this a while back and hadn't reviewed it as hadn't need to use it. I bought it for those emergency needs. So last night stuck in the middle of nowhere I push the start on the car and nothing happened. Wife immediately told me it was my fault for not replacing the battery but since the car had just been serviced and they told me it was in good condition (it actually isn't) I went to the back and grabbed this out of the box that it was still in. It was harder to get the cover off the positive terminal than using it. Once connected it charged in a couple of minutes and the car instantly started. I was then the hero as we didn't have to wait for AAA for a jump. Totally worth the money. Would be nice if it had a bag or something to keep it in but that is the only thing I can think of that would make it better.

I got the 550 amps original jump starter (js) RZ-550 from Rezervo a few years ago and the thing is a beast and works fine. Never had an issue with it. So my sweet wife always wanted one too and therefore we ordered this one here which has 100 amps less. But is also a lot cheaper. If the battery is completely empty then it won't help. But if you have still some power in there and just not enough to start by itself that js will definitely help starting it! Otherwise it can be used to charge it elsewhere and "pump" some energy into a depleted battery until it will start. Good for people who have their trucks/cars just sitting in the driveway with depleted batteries every now and then. If it doesn't start directly, just get the js charged with the other truck/car and "pump" it into the depleted battery. Of course if your starter, relay or something else is the issue it won't help though. Regarding reliability of this one here we shall see. But we checked it twice and it works fine so far. I just take off one star for the reason the charging consumes more time than advertised (100 sec.). Rather calculate with 5-10 minutes unless your battery is full (in which case you won't need a js). This one here also loses power faster than the Rezervo one. The Rezervo maybe loses 1v in a day. This one here loses 2v in a day. So the leakage of the used super caps seems a little higher. In regards of comparison to a battery js I'd definitely recommend a supercap js! You still have the ability to charge it elsewhere (and fast) and if the battery is not completely empty you can charge it on the car/truck where you need it. Easy and simple!

I use the Schumacher DSR 108 to start my old 19 Hp lawnmower. It put out a maximum of 274 amps (including the old battery). Excellent safety features. I ran many tests using my power supply set at 12 volts and 10 amps to recharge the DSR108. I used a carbon pile battery tester on the DSR108. I turned the amp knob as fast as I could and the unit delivered 270 amps that slowly declined to 0 amps in 7 seconds. A standard capacitor discharge curve. In the video you can just see the volt needle go from 16 volts to 2.5 volts over the 7 second discharge. I used the power supply to recharge the DSR108: It took just over 3 minutes to fully recharge, requiring 4.33 Wh and .50 Ah (the manual states .4 Ah). The only annoying thing is when you connect the battery to charge the unit the lights come on, but it does NOT recharge until you press the ON button. The lights are only showing the status voltage. So if it isn't working just press the on button until it does. The vehicle’s 12-volt DC port also works great. The Schumacher has 1.5 times output amp hours as the Autowit 2. Highly recommend

As long as the car battery isn't completely dead, just too weak to start <12v, this works really well. I think I've jumped a couple batteries that had 3v-4v, just takes longer to reach "ready" state. This worked on a Jeep Renegade 4 cylinder 1.3L turbo, Vw Golf R32 3.2 VR6, and a Ford Explorer V6. The box is a little bulky, but I don't have to worry about maintaining a charge on one of those compact Li-Ion jumpers.

Part of my job responsibilities include assisting stranded motorists. I am very experienced with jumping vehicles. I am familiar with and very attracted to this jump box due to it's benefits over a normal jump box. I do not like to charge my jump box and keep it fully charged in my trunk in FL heat waiting for it to explode. This product makes more sense for most people. I tried to jump 2 separate 4 cylinder vehicles on 2 separate occasions. On both occasions, the volts stopped climbing at 11 volts. On both occasions, I swapped the charger to a separate working vehicle to try to charge this product. Again, this product would not charge past 11 volts. Both times it did not jump start the dead vehicle. I then jumped both vehicles with normal jump boxes. This product is an expensive waste of money. I really wanted it to work out but it did not.