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Portable jump starters like the NOCO GB40 provide the convenience of on-demand power when the battery runs low. Instead of waiting for a friend with jumper cables or roadside assistance, open the hood, connect the unit to the battery, and start the vehicle. Portable jump starters, like the NOCO GB40, are also ideal for winter emergency kits and extended road trips.
Officially called the NOCO Boost Plus GB40, the 1,000-amp unit fits nearly all lead-acid car batteries, most gasoline engines, and the smallest diesel powertrains. It’s easy to store as the entire unit with clamps and accessories weighs less than 2.5 lbs. A built-in 100-lumen flashlight, built-in charging bank, and helpful security features make the GB40 a good value for its $100 price.
Here we will cover the main features of the NOCO GB40 if you are looking for a portable jump starter.
NOCO GB40 in depth: what it offers
The GB40 comes with detachable heavy-duty clamps, a 40-inch micro USB cable for charging, a 12V 2.1-amp USB car charger, an owner’s manual, and a microfiber storage bag. The GB40 is only partially charged at the factory, so NOCO recommends fully charging it before use. Using the included micro USB cable and a USB wall charger, our GB40 took about three hours to fully charge. According to NOCO, the GB40 can provide up to 20 jump starts on a full charge under ideal conditions.
The GB40 has an internal 24-watt-hour lithium-ion battery with natural convection cooling. Meanwhile, the case’s rubber covers for the 12V and USB outlets are IP65-rated to protect against dust and water. NOCO designed the GB40 to withstand temperatures as low as -4°F (-20°C) and as high as 122°F (50°C).
Battery and Vehicle Compatibility
The NOCO GB40 will connect various lead-acid batteries, including wet cell, gel, maintenance free, enhanced flooded, and absorbed fiberglass (AGM) batteries. Given the wide range of lead-acid battery compatibility, the GB40 is suitable for the vast majority of vehicles on the road today, whether new or gently used. The GB40 will drive gasoline engines up to six liters, which covers a wide swath of half-ton trucks and all small and midsize SUVs. Similarly, the GB40 will power a smaller diesel mill (up to three litres) on a cold day.
Also useful in the garage or shed to jump up any dead grass and garden batteries. Whether you’re going camping or hitting the trails, the GB40 can also be used for almost any RV, marine, four-wheeler, or snowmobile battery.
Precision Clamps and Jumper Cables
One of the main features of the GB40 is the heavy-duty detachable clamps (listed as “precision clamps” on the spec sheet). The spark-proof shark-style design allows the clamp to bite into batteries and terminals of different shapes and sizes. The only potential drawback is the relatively short length of the cables, which can be a drawback depending on where the battery is located under the hood (although the shorter cables do make storage easier).
integrated flashlight
On the right hand side of the GB40 is a 100 lumen flashlight (bulbs are located on each side of the 12V outlet for the jumper wires). Press the bulb button on the unit to access seven different modes, including an SOS beacon and emergency strobe light. Constant-on modes have three different brightness settings, from highest to lowest.
While the convenience and safety aspects of the flashlight probably go without saying, we here at the office had the opportunity to use it during an afternoon snowstorm. Just as we received our GB40, the Detroit metro was hit by a storm that produced ice and strong winds, downing trees and power lines. We use the flashlight to go down the stairs before leaving.
load bank
After I got home that night, the GB40’s USB charging port came in handy. On the left side of the unit are two 5V 2.1A ports: USB input for charging the GB40 and USB output for charging devices such as tablets and phones. The built-in load bank makes the NOCO GB40 more versatile and opens up other potential uses for the unit beyond auxiliary batteries.

battery management system
The GB40 is based on a proprietary software platform known internally at NOCO as the Battery Management System or BMS. As described by NOCO, the BMS is responsible for key security features and creating a “fool-proof” product for customers. With the BMS, the GB40 only outputs when it recognizes that its cables are properly connected to a battery. For example, if it is accidentally connected to the wrong terminal (reverse polarity), the GB40 will not activate. Similarly, if the polarity is correct, but one of the clamps is loose, the BMS prevents the GB40 from delivering power.
With proper connection, the white 12V LED will illuminate on top of the unit. The GB40 will make an audible click, indicating that it is safe to jump the battery.
Instead of hitting everything it plugs into to the max, the NOCO GB40 only delivers the juice required by the battery that needs a jump. Essentially, you can tell the difference between a lawn mower battery and a truck battery and adjust your power supply accordingly.
Is the NOCO GB40 worth the money?
The safety-focused compact design combined with the flashlight and charging bank make the NOCO GB40 a winner. While a dead car battery can only happen occasionally, the GB40 is something you’d rather have and not need than need and not have. If you want a portable jump starter for your emergency kit, the GB40 is a good choice. NOCO has more powerful units available, but the GB40 will suffice for most vehicle owners and is reasonably priced for its performance.
We also have a Shell 1200A jump starter, but the NOCO GB40 feels more durable with its hard protective casing and the internal battery seems to last longer. Our Shell is still a good unit, and we still plan to use it, but the GB40 is a welcome addition to our office garage. As of this writing, the NOCO GB40 is available on Amazon for $100.
Carl Anthony is Managing Editor of Automoblog and a member of the Midwest Automotive Media Association and the Society of Automotive Historians. He is a member of the board of directors of the Ally Jolie Baldwin Foundation, a former president of the Detroit Working Writers, and a loyal fan of the Detroit Lions..
Photos: Alex Hartman.