3 1/2" Aluminum (NOT MINI SIZE) LOUD Emergency Survival SOS Whistle Camping Hiking Keychain 3 1/2"L by 1/2"W whistle size (not Mini size)1 unit = quantity of 2 whistlesGreat on college campusPerfect for evening walksDurable Aluminum keychain whistle with detachable hookNote: available colors - black, gold, silver, purple, blue, hot pinkYou will receive 2 whistles - Random colors will be shipped unless specific colors is requested!