The Pro model has electromagnetic dimming, which allows it to change the transparency of the glass - from fully transparent to fully opaque.
Xreal Air vs. Viture XR: Display Glasses - Video - CNET
Choosing the Future: RayNeo Air 2 vs Xreal Air 2 Glasses
Xreal Air 2 and Air 2 Pro glasses go global with better displays and lower weight - news
Xreal Air 2 Pro AR Glasses Review: Minor Upgrade
XReal Air 2 Review
Air2 Pro. The ultimate wearable display experience., Ships in 5 work days., Explore >>, Connectivity:, USB-C DisplayPort, Items Included:, Glasses
XREAL Air 2 Pro
Xreal Air 2 Pro Review
Xreal Air 2 review: a step up from good AR glasses to excellent - PhoneArena
Xreal Air 2 Review: Greatly Improved, Well-Rounded AR Glasses
XReal Air 2 Pro: A Leap Forward in Consumer Grade AR Glasses Technology - Men's Journal Tech Trends: Stay Ahead with Tech News, Rumors & Deals
I demoed Xreal's AR glasses for spatial computing and they're better than I expected
XREAL Air vs. Air 2: Are the new AR glasses actually better?