Generally use as supported hand paddle that keeps wrist in place. Upon purchasing I thought it might do a better job of helping keep elbow up.
These paddles really added a strength building component to my swim workout that was missing. They are great at improving form, as they make you quite aware of the angle at which your hand enters the water. I haven't quite figured out the little black strap that is supposed to hold the paddle to your fingers. It falls out. It is possible that I am attaching it improperly, but I still feel that the paddle does what it is supposed to do and is a high quality product.