New translucent color-coded sizes. Invented by World Record Masters swimmer and former ASU coaching great, Ron Johnson, the Catalyst helps improve stroke technique while building strength. It's patented unique keyhole design helps more evenly distribute pressure while improving water feel and reducing shoulder stress. Constructed of lightweight, injection molded, UV resistant polypropylene. Paddle has smooth edges and multi-hole strap design for custom centering on hand. Be sure to contact your coach for correct sizing.