Part of GEAR AID's complete line of replacement parts, the Whistle Buckle is a no-sew solution to buckle repair. Use this standard 3/4” buckle kit to easily replace broken or missing sternum strap buckles. Made with durable plastic materials, it also works as a safety whistle that's handy to have during an emergency. So, be prepared. Don't forget to bring a Whistle Buckle in the backpack before venturing outdoors.