The Oneplus Concept One will be officially revealed next week, but OnePlus couldn’t wait until then to tease what makes its concept phone special.

OnePlus is using electrochromic glass to hide the Rear Cameras on the Concept One. Then when you’re ready to snap some photos, the glass changes and reveals what appears to be a trio of rear cameras.

This glass uses organic particles to create tints of color when subject to an electrical field. When a different voltage is applied to the glass, the light transmission properties are altered. This allows the glass to change from transparent to translucent and back again.

“By leveraging this dynamic glass solution, the OnePlus Concept One is able to maintain a clean and unbroken back cover while simultaneously delivering a premium and unobtrusive hand-feel experience to its users,” OnePlus explained.

A report from Wired confirms a few more details about the OnePlus Concept One. The phone was made in collaboration with McLaren — the same special glass that hides the cameras is also used on some high-end car sunroofs — and it has a papaya orange leather back with stitching. 

The OnePlus Concept One has the same camera specs as the OnePlus 7T Pro McLaren Edition. That means it’s got a 48MP main sensor, 16MP ultra-wide angle camera, and an 8MP telephoto cam.

Finally, it’s been confirmed that OnePlus has no plans to sell the Concept One anytime soon, so most folks will have to settle for watching the disappearing cameras in videos online.

One of the popular trends in mobile over the past couple of years is adding more and more rear cameras to devices. Most phones nowadays have at least two, with others having up to five cams on their backsides. Some folks might not like that look, thinking it can make the back of a phone look cluttered or busy. With this OnePlus Concept One, the rear cameras are hidden when note in use, giving the back a cleaner look.