Kids are sure to love this faucet that changes the water color based on the temperature. It's so straightforward a child can understand it: blue means cold, red means hot (over 89 degrees). It's certainly useful for preventing scalding and accidents. The faucet light replaces the aerator on the end of an existing faucet. The patented device is 2.5" long x 1.25" in diameter and includes a set of two universal adaptors that fits virtually every U.S. faucet. It can be purchased online from the Hogwild Toys web site.