Apple’s long-awaited Vision Pro headset will include a new authentication system specifically designed for the world of virtual reality.

Announced at Apple’s WWDC 2023 keynote event, Optic ID uses a person’s iris, which Apple says is always unique even when you’re talking about identical twins, to unlock the headset. Just like with Apple’s other biometric identification methods, like Face ID, Optic ID data is encrypted and never leaves the device. 

The authentication system also is compatible with features like Apple Pay, app store purchases and password autofill, Apple said.

Meanwhile, Apple also said Monday that it engineered privacy and security into the mixed-reality headset by designing it to keep what a user is looking at private, noting that what a person chooses to look at has the potential to give away what they’re thinking about.

Apple said the data is isolated in a separate background process, so apps and websites can’t see what a user is looking at. It’s only when a user taps their fingers or enters a response on another Apple device that the data gets communicated and processed at the system level.

The Vision Pro is set to go on sale next year for $3,500.