This toy has a rotating blade inside. When you blow or suck air through either end of the tube, the blade spins, producing a high-pitched siren-like sound. Similar to a regular whistle, the pitch of the sound increases with the force of your breath. Could also be used to improve oral function for children and the elderly. Two unused pieces in a set, colors are random. *This is an imported toy.* Also suitable for practicing speech in children. #Whistle #Siren #Whistle #SirenWhistle #Speech #Practice #Therapy #SpeechTherapy