Well, they seemed made pretty well. OM has a video on their site of how they work. The basics are that you need something like an OM or SCWD which changes the water flow. When the water flows into the pipe that has a revolutions on it, the unit is forced down along a track which turns the nozzle 45 degrees. Then when the water stops the unit floats back up.
The flow you get is based on the type of revolution you get. You can get a single outlet with the nozzle at 15, 30, or 45 degrees, a unit with 2 nozzles, or a unit with 3 nozzles. The multiple nozzles are all on whenever the revolution is on. You can custom order units as well.
I got 2 units with a single 30 degree nozzle and 2 units with 3 nozzles one each at 15, 30, and 45 degrees. I have 1" piping and the revolutions came threaded. I got the PVC connectors yesterday. Still haven't gotten them installed yet but soon. I can post more once they are installed.
I know Squidd was concerned that they might cause "jiggle" of the water rather than good water movement. I'll post what the final results are once I get them installed. I have visitors coming this weekend so it might have to wait until next week :-(