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There’s nothing worse than being out on the open road when your tire pressure light comes on. The availability of air pumps at gas stations vary from state to state, and they’ll often leave you struggling to round up quarters. Some retailers offer free air, but there’s not always a guarantee there will be one within a reasonable driving distance, especially if you’re racing the clock and losing air with every mile.

Fluctuations in air temperature — something our cars are increasingly exposed to — can also affect tire pressure.

There are a variety of portable tire air compressors available these days. They’re small enough to keep in your trunk and often come with a 12V outlet so you can power up via your car’s dashboard lighter. One particular highly-rated model is discounted today, and when you click the additional 20% off coupon (yellow model only), it’s just $22.38 in your Amazon cart — a total of 40% off the typical price of $36.99.

This shoebox-sized device attaches easily to the valve of your SUV or car tires and will begin inflating at the push of a button. The machine also offers the ability to pre-set your desired tire pressure, and it will automatically shut off once your PSI number has been reached.

A host of other features — including a lengthy 9.8-foot power cord and a built-in LED light — make the pump an convenient option to keep in your trunk in case of emergencies. It also comes with three different nozzles intended to inflate sporting equipment, inflatables and bike and ATV tires. (It’s worth noting that the maximum tire pressure is 150 PSI, so it’s not intended for truck, vans and off-road vehicles with larger tires, and it will need a cooldown period after 10 minutes of continuous use.)

At 40% off, it’s a very low-cost investment in your peace of mind. And with a 4.5-star rating and over 27,000 five-star reviews, it’s a clear customer favorite. If you’d like to see how this device helped other reviewers out, check out some relevant Amazon reviews below, or just scroll all the way down to get one for yourself.

“We had a vehicle develope a slow leak in 1 tire. We live in a rural area about 10 miles from the nearest gas station, so this compressor resolved our issue temporarily. The Vaclife allowed me to set the desired PSI pressure, and automatically stop when that pressure was obtained. We had the tire serviced and repaired and all was good… We now have 2 Vaclife compressors, and I will be ordering a third for my work vehicle. As an added bonus, we had several bicycles cleaned up and repaired during 2020 covid summer and this compressor is the only one that will actually inflate the new tires that were used on two of the bikes.” — Paul Volker

“I was driving the other day and one of my tires sensor flashed on my dashboard saying PSI was low. I wasn’t in a familiar place and didn’t want to take the time to find a Costco (as that’s where I get my tires done) or any other place for that matter! And then… I remembered I had this in my trunk and hadn’t used it yet!! I pulled it out, followed it’s simple instructions and it all worked! I was very impressed and I am thankful to have this in my car knowing I can count on it if I experience this again! :)” — Bree

“I’m not at all handy, mechanical or patient haha. Esp. the latter. However, even I figured this out super fast. Very user friendly, sleek and sturdier than I thought. Nothing really flimsy or cheap feeling/looking about it. Love the features- esp. how it instantly reads your current tire pressure and stops automatically once tires are filled to desired level. Key for me is that peace of mind knowing you have it in your trunk or wherever and NOT having to fret if the low tire pressure light comes on abruptly in a bad area etc….then frantically looking for a gas station, deal w/ quarters, old busted machines. May be rare but it’s when not if for everyone and quite stressful in the moment. Recommend!” — jamiko1230