Sound heightens curiosity in fish and triggers investigation. These lures actually produce sound frequencies that are harmonic, uniform and "in tune" with nature. The secret of sound combined with the patented Rapala "wiggle" is what makes this lure so effective. Rip it fast or run it slow; either way, it sounds like a dinner bell to fish. The RattlinÆ Rapala is quite heavy for its size and casts well even in windy conditions.