(KODE/NEXSTAR) – There are multiple buttons and dials and toggles in your vehicle. But there’s one button that could be especially helpful amid sweltering heat and widespread wildfire smoke impacting many throughout the U.S. — and it may help you save on gas.

On most cars, trucks, and SUVs, you can find an “air recirculation button” in the climate control dashboard. The button has an arrow in a half-circle within the outline of a vehicle on it.

Never noticed it before?

The air recirculation button has a relatively simple function, Tabitha Ruhl, manager of Joplin Transmission and Auto Center told Nexstar’s KODE. It stops your vehicle from pulling in outside air to cool you off and instead recirculates the air-conditioned air already inside your car.

This can also help boost your air conditioning, which can make the cabin of your car cooler, quicker. For those living within the heat dome — currently impacting Texas, Missouri, Oklahoma, the Mississippi Valley, and portions of Florida — this may be especially beneficial.

Using the air recirculation button can also keep pollution, exhaust fumes (and other unfortunate smells), and pollen out of your car. And for those in states blanketed by Canadian wildfire smoke — Minnesota, Wisconsin, Illinois, Iowa, Indiana, Michigan, Pennsylvania, and New York, as of Tuesday evening — this could mean having cleaner, easier-to-breath air in your car.

Even if you aren’t impacted by record-high heat or hazy wildfire smoke, the air recirculation button can still be a good bang for your buck — literally.

As Ruhl explained, when your car has to pull in and cool (usually hot) air from the outside, your vehicle has to work harder, which can mean using more gas. But if you recirculate the already chilled air in your car’s cabin, your vehicle should be more fuel efficient.

Because the air recirculation button goes hand-in-hand with a vehicle’s air conditioning system, you’ll likely want to use it when it’s the temperature outside is greater than 75 degrees Fahrenheit.

While the recirculation button is great for the summer months, it may be best to avoid it in the winter or when your windows become foggy.

“Anytime you’re using defrost, it’s best to not have that button on. Also, using it while you have your heater on isn’t going to do anything for you vehicle,” said Ruhl.