The sound is associated with Das Boot, the 1981 German submarine film directed by Wolfgang Petersen. Online, short alarm cuts from the movie are often shared as ringtone clips, soundtrack snippets and dramatic meme audio because the tone is instantly recognizable as a naval emergency signal. It still gets used because it communicates danger and tension in less than two seconds, making it useful for quick edits, status videos and reaction posts where creators want a cinematic wartime alarm feel.