I've never heard of them, came up with nothing with google search. What works best for me is a crappie/perch rig. Throw away the snelled hooks that come with it and tie small jigs or teardrops(bright green is my fav) on a 2-3" leader and hang off the wire. Short leader keeps it from tangling around wire. Tip the jigs with live minnows. When you detect a bite set the hook, not too hard as to jerk off other minnow, and let it sit for a few seconds, good chance the commotion will cause another perch to bite the other minnow. Give it a try and you may find yourself catching two at a time. Good Luck.
