: Primarily associated with 1080p (Full HD) video streams [18, 23].
: Typically a "video-only" stream, meaning it must be combined (muxed) with a separate audio stream (like itag 140 or 251) for full playback [28]. Usage and Issues
: Users of yt-dlp and similar tools may see this ID when listing available formats for a video [18].
: These "Premium" or high-bitrate itags (like 616 and 617) are part of YouTube's efforts to provide enhanced quality for certain viewers or devices [26, 30].