The Volkl Co-poly Trial Pro Pack contains four incredible Volkl co-polys. All of these strings are durable and provide exceptional precision and spin to big hitters. Volkl Cyclone is one of the most playable and complete co-polys available. It has a gear shape with sharp edges for added bite. This one offers a comfortably crisp feel and just enough pop to finsh points. Volkl V-Torque has three longitudinal grooves that form sharp edges for gripping the ball. It offers a very precise response along with above average comfort for a firm monofilament. Volkl Cyclone Tour features a twisted gear shape for extra spin. We think this is the softest and most powerful of the bunch. Great for players who want a livelier and more comfortable control string. Volkl V-Pro is the most low-powered of the group. This round poly provides outstanding control on full swings.