Toot! Toot! The whistle was first invented in China where night watchmen blew into the tops of acorns to alert townspeople. Today we have thieves, lazy husbands and people in bike lanes to alert. Sometimes you need a high-pitched, loud signal from a device when your voice is not enough. This style of whistle is called a "pea whistle," as there is a pea-sized ball inside. Made by the only American company that still produces metal whistles. It is really loud - so if your ears are sensitive, please be sure to put your earplugs in before using it indoors. Indestructible - it will last. The chain makes it easy to keep around. I find it handy for getting Marco out of bed in the morning. Oh, and it's super fun to use on people who leave their engines running while parked. Citizen's arrest! They get so freaked out, they actually turn the key in the ignition to "off"!