Police radio beeps come from the squelch and channel tones used on two way radios, where a short chirp signals that a transmission is starting or ending. The double version, called doppio in the original upload title, became a staple soundboard clip because it is clearer than a single beep and easy to recognize at low volume. Editors adopted it for gaming, roleplay videos and short form comedy, where it quickly tells viewers that an officer is about to speak without needing any actual dialogue or sirens.