That’s the capability to connect AirPods Max to analog sources such as the inflight entertainment on an airplane which, almost universally, still requires a cable link to a 3.5m

According to Apple, a new firmware update will enable AirPods Max to access 24-bit, 48kHz lossless audio. Lossless audio also extends to Personalized Spatial Audio to deliver a more sonically accurate, uncompressed, and immersive experience, especially with the more than 100 million songs in lossless audio on Apple Music.

Addition of lossless and ultra-low latency audio and an optional new USB-C to audio jack connection Apple's dropping a firmware update for the AirPods Max in April that will bring lossless audio and ultra-low latency audio to the headphones.