The Azuma Shaker Z Knock Knock Lipless Crankbait offers a unique sound that fish are not accustomed too. Built with a single lead internal rattle, the Knock Knock produces a deep thud knocking sound that is much lower in pitch than traditional bb's or a single tungsten rattle for a more subtle presentation to trigger more bites from finicky fish. Features Single lead internal weightOversized belly creates powerful vibrationExtra sharp trebles