A level slider, as in adjusting the volume on a mixing console.
Most platforms depict a silver and black channel fader with tick marks on it, set to various levels.
Apple and Google have the highest setting at 11.
Commonly used in various content related to audio recording and production, as well as music more generally.
May also be used in the figurative sense of level, as in the next level.
Due to its appearance, some people may use this emoji to represent the Christian cross.