Keep your dog engaged in fetch with the Chuckit!® Sonic Fetch Pack Duo! This fetch pack combines two of Chuckit!'s best-selling fetch balls - Chuckit! Ultra Squeaker and 1 Chuckit! Super Crunch Ball - into one awesome fetch pack your dog will love! Designed to attract and engage your dog in fetch, the Ultra Squeaker gives off a loud squeak when used while the Super Crunch Ball features a patented crackle sound that crinkles and crackles and will not break down with use. Made for fetch, both balls are made from safe, durable materials that are gentle on your dog's mouth and are compatible with medium Chuckit! Launchers. A great value pack set to upgrade fetch time by activating your dog's natural curiosity.