Make Fetch Happen? with Chuckit!'s? Sniff Fetch Balls! Infused with peanut butter and bacon, these fetch balls attract your dog to them with their delicious & mouth-watering scents, making it easier for your dog to find during games of fetch. Made from the same durable natural rubber with an extra thick core that Chuckit! fans have come to love, Chuckit! Sniff Balls are launcher-compatible with medium Chuckit! Launchers have a high bounce that keeps your dog engaged in play.