Jigglers are not toys, rather they are therapeutic devices to be used with adult supervision. May contain small parts, or the potential for small parts exists. Not to be used in water play. These are the only continuously “on” chewable, durable facial and oral massagers that provide the calming and organizing input of low intensity vibration. To turn on, simply give the head a twist. Secure battery compartment makes Jigglers safe for infant use. Sold as a set of two, one kangaroo and one parrot. Requires two AA batteries, included.