Amazon Prime Day deal: The Noco Boost Sport GB20 portable jump starter is currently discounted by 15%, bringing its normal $65 price tag down to just $55 bucks. The GB20 packs enough cranking power for most passenger cars and small SUVs, but owners of big trucks, V8s or diesel-powered vehicles can also find Noco’s larger GB40 jump starter discounted to $80 which is 36% off. Either way you go, today’s Amazon’s Prime Day sale discounts make this a great time to add a little safety and security to your roadside kit.

Few things are more inconvenient (or scary) than going to start your car at night only to find its 12-volt battery has gone flat, especially if there’s no one around with cables to give you a jump start. That’s why for years I’ve been recommending that drivers keep a small portable jump starter in their trunk or emergency kit to quickly get themselves restarted and back on the road. The Noco Boost GB20 is one of my most frequently recommended models due to its compact size, excellent build quality and reliability and, most importantly, its sweet-spot cranking power for most passenger cars.

Here’s why I keep recommending the Noco Boost

The Noco Boost is extremely small, not much larger than an airline-sized USB battery bank. It ships with a set of clamps for attaching to your car’s battery and a small bag to keep everything together. Ideally, you won’t have to use the GB20 frequently, so its small size is a boon for tucking the jump starter out of the way in your car’s trunk, glove compartment or console. The unit charges conveniently via USB type-C and, in my experience, does a great job of sustaining its charge for months in storage, so it’ll always be ready when you need it.

Using the Noco Boost GB20 is even easier than jumper cables. Simply connect the positive and negative leads to the positive and negative terminals on the car’s battery, power the GB20 on and then start the car. Once you’re up and running, disconnect the Noco Boost and toss it back into your emergency kit — no worrying about crossed cables, no flagging down strangers for a jump. There’s even a built in 100-lumen flashlight to help you see what you’re doing at night.

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The Noco Boost can also be used to charge and power your phone or other small gadgets in a pinch thanks to its weather-sealed USB type-A port, which is a nice bonus if your emergency isn’t a dead battery and you need to call for help.

The right size for the right price

Rated to deliver up to 500 amps of peak power at 12-volts, the Noco Boost GB20 claims to deliver up to 20 starts per charge for gasoline engines up to 4.0-liters. I’ve never needed to jump 20 cars before getting back to a USB charger and most of today’s passenger cars and small SUVs sit handily under the 4-liter mark, making the GB20 the sweet spot for most drivers. Marked down by 15% today, you can add it to your cart for just 55 bucks.

However, owners of big trucks, muscly V8s or diesel powered vehicles may find themselves needing more cranking amps. Fortunately, Noco’s entire line of vehicle power products is on sale. For trucks, I recommend the 1,000-amp Noco Boost GB40 which is discounted to $80 or 36% off its regular price. This upgrade isn’t all that much larger than the GB20, but claims to crank up to 6.0-liter gasoline or 3.0-liter diesel engines.

For the ultimate in roadside readiness, Noco’s Boost Air AX65 combines a 2,000-amp portable jump starter with a battery-powered air compressor for your car’s tires. It’s also deeply discounted today at just $210, a savings of $90 off the regular price.

Why these deals matter

Finding a good portable jump starter is an easy way to add peace of mind to your or your loved one’s trunk, especially if they drive an older car or have a habit of accidentally leaving their vehicle’s lights on. Taking advantage of these Prime Day deals at Amazon can also leave you with more room in your budget for the rest of your emergency roadside kit.