Shield your pup from fleas and ticks without using harmful chemicals. The Max & Molly Soundshield 24/7 UltraSonic Tick & Flea Repeller Dog Tag uses cutting edge technology to safely and effectively protect your pal from fleas and ticks. The device emits ultrasonic sound waves that are inaudible to humans and animals but irritate the nervous system of ticks and fleas—so they stay away from your dog. Comes with an array of features including a silicone security strap, waterproof IPX7 submersible, replaceable battery, and a blinking indicator light.