I think they're money is made on deep water bites. I also agree with the other guys. Can't hurt, but it can help. I don't throw one without em, because a month ago me and friend went night fishing. I used them and cleaned house, on the other hand, my friend didn't use them (same bait & color) and got skunked. Too many variables involved to say it was the rattles, but it helps my concfidence. And that reason being my 2 personal best have been in the last 2 months, both had rattles inserted.