3 Medical ID Key Chain Whistles. This is a new set of 3 medical ID key chain whistles. These can be used for medical emergencies. The ends unscrew to hold your emergency medical information. They have the words "In case of emergency open capsule". Each measures approximately 3" (76 mm) long and 7/16" (11 mm) in diameter. We work hard to update our descriptions and pictures of our merchandise. As part of a process of ongoing innovation by our suppliers, newer versions of the item shown may be shipped before we are able to complete an update. As a result there may be a slight variation in color and design.