The new 2021 Ford F-150 has plenty of new features on display, including lie-flat seats and a built-in desk, but one of the most significant is hiding in plain sight.

If you’re checking one of the pickups in a couple of weeks when they arrive at dealers, you may notice a small black panel on the driver’s side door pillar. Here’s what it looks like:

It’s part of an optional prep package for Ford’s new Active Driver Assist feature. So, what does it do?

Well, it's covering one of three sensors used to monitor the driver to make sure they’re keeping their eyes on the road in case of emergency. The other two are hidden beneath the black plastic on either side of this row of buttons on top of the infotainment system screen:

A Ford spokeswoman told Fox News Autos that there’s a camera to the left of the buttons, while the one on the right and the door are sensors that use invisible infrared light to see through sunglasses to make sure your eyes are open. Don’t believe it? Check out this video we shot that reveals them at work:

Cadillac’s similar Super Cruise hands-off system uses an assortment of sensors clustered in a pod on the steering column behind the wheel, while Tesla’s Autopilot doesn’t currently have any visual monitoring and technically requires a driver to keep touching the wheel to prove they are alert.

(Cadillac)

TEST DRIVE: THE 2021 FORD F-150 POWERBOOST HYBRID LIVES UP TO ITS NAME

Active Drive Assist is launching in the F-150 and Mustang Mach-E and is expected to be ready to roll down the highway on its own in the second half of 2021.

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