Trump® Mouth-Operated Foghorn
This easy-to-use foghorn combines the powerful blast of a gas foghorn with the simplicity of a mouth horn. It delivers over 100dB with little effort, simply by blowing into the side hole.
It operates on the vibration of a plastic diaphragm, which can easily be replaced with any thin plastic film. (Two replacement diaphragms are included.) It's durable, ecologically friendly, rustproof and economical. It never needs recharging, and it virtually can't be lost because it floats!