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Lifewire / Tony Mitera
Huge battery capacity
Built-in air compressor
Easily accessible 12V DC power output port
Large and heavy
Few accessories, with no place to store them
Slides around when the engine starts
If you can find a secure place for its bulk within your vehicle the STANLEY J5C09 is both a jump starter and a compressor, and largely succeeds at both.
It’s hard to look at something as relatively large as the STANLEY J5C09 and not wonder where it’s going to fit into your vehicle. It’s a big unit that touts a lot of features, but all that heft seemed like it might make it harder to keep in a car without it taking up a bunch of space or rolling around a trunk. Nevertheless, we opened the box, charged it up, and began to test how well it held up against a car with a dead battery.
The design of the STANLEY J5C09 borrows from the same black, grey, and yellow design accents that the brand is known for. The unit's a bit smaller than most luggage, with a handle on top for ease of carrying, but it's massive compared to other starters. The front of the unit contains all the controls and additional power ports, while the rear of the unit has the air compressor hose and a small pouch for the 12V charging cable. Each side of the chassis contains one of the two jumper cables and clamps which wrap neatly around some built-in parts of the case before clamping down to keep them in position.
At a whopping 18 pounds, it's also heavy. The combination of the two makes the device difficult to find a good spot to keep in a vehicle that doesn’t let it roll around, and even then, it's going to take up some cargo space with its sheer bulk. There’s also no good place to keep the unit’s manual along with the unit, so you're better off stashing it in the glovebox.
The STANLEY J5C09 is a dual-purpose device, a jump starter that doubles as a compressor. To test out the jump start side of the equation, we depleted the battery of our test vehicle, a 2011 Hyundai Elantra, down to a mere 10 volts.
The unit's a bit smaller than most luggage, with a handle on top for ease of carrying, but it's massive compared to other starters.
To get the unit into position, you lift it and set it down wherever you can atop the engine bay. After unclamping the unit’s two terminal clamps, the long cables leave plenty of slack to reach wherever you need.
After clamping the red clamp onto the positive terminal of the car’s battery and the black clamp onto the negative, you simply need to turn the unit on with the knob on the front. Once done you can immediately get back into the car and attempt to start it. The terminal clamps are small, and easy to get clamped onto the battery, even in relatively tight spaces.
The unit's also a capable air compressor, able to air up your vehicle's tires or other recreational items using the provided adaptor. At the rear of the device, there's an air hose that unfurls from its storage area and has a threaded end that you twist onto the valve stem. After a few twists, the connection is secure and airtight, and you can turn the compressor on with a switch on the back.
The unit was able to provide a reliable jump start every time it was tried, but not without some caveats. In our experience, the vehicle started immediately every time, though just as often we watched the whole unit dance due to vibrations and begin to slide down the engine bay. With its size and smooth underside, it’ll slide as soon as the engine starts and begins vibrating, and extreme care must be taken to make sure you put it somewhere where it won’t slide off.
The compressor feature has some flaws as well. As the compressor does its work you can keep an eye on the pressure using the unit’s pressure gauge. However, the gauge is small and somewhat hard to read in the best conditions, and almost completely illegible in the dark. Additionally, the hose is only barely long enough to reach the top of an average-sized tire if the stem happens to be at the top. On a larger tire, such as a truck tire, the hose simply may not be long enough to reach without first putting the unit on something else to elevate it and bring it closer.
The unit was able to provide a reliable jump start every time it was tried, but not without some caveats.
Performance is significantly smoother when it comes to USB charging. The USB port provides a nice 1,200mAh charge rate which is pretty snappy. On the tested unit, it was a little difficult to plug a USB cable in as it had a very tight fit, but it did work.
The DC port provides 12V 5A power, but any portable device using it must have a 12V power port connector of their own. Curiously you can also charge the unit back up using that same power port by using the provided “port-to-port” cable and plugging it into a running vehicle. The cable is quite short though, so you may end up having to put the unit in the passenger seat and buckling it in like a small child.
Mounted on the shoulder of the unit is a small flashlight that attaches to the case on a ball joint. This allows you to put the unit on top of the engine bay, orient the light to illuminate the work area (generally your battery), and be able to better see what you are doing. The joint isn’t incredibly flexible but has just enough freedom of movement to make it a useful feature. It, like everything else, draws power from the unit’s main battery so you don’t have to worry about keeping it fresh for when you need it.
If you need a compressor and can accommodate the incumbent weight and bulk, this price is pretty reasonable.
You can find the STANLEY J5C09 available online for around $110, which puts it slightly on the more expensive side compared to other jump starters we’ve tested. If you need a compressor and can accommodate the incumbent weight and bulk, this price is pretty reasonable.
NOCO Genius Boost Pro GB150: NOCO’s Genius Boost Pro GB150 is another bulky starter that we tested. The STANLEY J5C09 has the edge here as it not only offers better charging of portable devices, but it also costs roughly a third as much as the GB150. It may not have a great flashlight, and it's harder to keep in a vehicle, but the high price of the NOCO unit simply may not be worth it.
Beatit BT-D11 800A Peak 18000mAh 12V Portable Car Jump Starter: Against more compact competition, the sheer bulk of the STANLEY J5C09 becomes a problem. If you really want the air compressor and DC power output, and can handle the size of the unit, the STANLEY option is a logical choice. However, we tested the Beatit BT-D11, which is not only smaller, but less expensive, and much easier to stash in a car for emergencies.
Interested in checking out more options? Take a look at our roundup of the best portable jump starters available.
Too big for its own good.
It isn't hard to imagine good use cases for the STANLEY J5C09 over other jump starters, but they're awfully specific. If you have a vehicle where you can accommodate the unit’s size and weight, need a compressor, and can make use of the DC power port, this unit fills that niche. It just doesn’t do as well in charging other devices, and its sheer bulk makes it impossible to easily tuck it away in smaller vehicles.