Georgia cubes with modifications. The modifications are build them with "legs" so they are up off the bottom a foot or so and have "hoops" that form "rainbows" above the structures.

To make it easier to handle the cubes when placed from a boat don't attached the weights (usually a couple pieces of 6 inch pvc filled with concrete) until you are ready to let them sink, then use big heavy duty zip ties and secure the weights to the bottom bar of the cube.

Crappie (and other fish) will use these structures and you will not lose jigs on these like you do cedar trees.

ClearCreek