The Bayou Rattler Products Sonar Ballzz are an acoustic line lure accessory producing the "natural sound" of underwater prey. Each ball is a waterproof sphere with two inner chambers, equipped with three stainles steel pellets per chamber to produce a constant subtle sound to attract fish. Sonar Ballzz can be combined with any line, dead, or artificial bait to enhance your presentation with a natural sound. Add to your line at any point, inside soft lures, worms, or to any jigs or rigs. Proven effective in saltwater, fresh water, ice or fly fishing. Features Produces "natural sound" of underwater prey Works with any bait or lure Proven effective in multiple environments