Callaway X2 Hot Plus Golf Balls Optimized Aerodynamics For More Distance Based on Your Swing Speed: Specifically engineered HEX Aerodynamic design has been engineered to optimize lift and drag for moderate swing speeds of 90 MPH and above to increase distance Straight Ball Flight: Low spin reduces hooks and slices for moderate swing speeds Softest Multi-Layer Design: Trionomer cover and fast tech mantle designed to produce maximum ball speed while providing incredible feel and control Two Color Options: X2 Hot + is available in traditional White or the newly formulated Optical Yellow for hotter visibility in the air or on the ground