Just a push of a button provides a loud, clear and consistent sound Utilizes a push button, which offers a hygienic solution for multiple operators Provides a loud, clear and consistent sound every time Give verbal commands without a whistle in user's mouth Fox 40 Electronic Whistle has three distinct tones that can be aimed in specific directions: Off / Tone 1 / Tone 2 / Tone 3 100 dB Requires one 9v battery Fox40 Fox 40 Electronic Whistle in Black.