CALLAWAY HX HOT DOZEN BALLS Ball speed is the key to extra distance. Additional yardage can be achieved either through added clubhead speed — a difficult proposition for most golfers — or through added ball speed. For the HX Hot Golf Ball, Callaway Golf design engineers focused on finding ways to increase ball speed while adhering to United States Golf Association (USGA) rules limiting initial ball velocity. They came up with a ball that rockets off the clubface at impact, achieves major hang time due to the revolutionary and now enhanced HEX rodynamics, and has superior feel because of the super-soft boundary layer between its hot core and rodynamic cover. The new HX Hot Golf Ball boasts significant improvements over traditional 2-piece distance offerings. The new, highly resilient core — essentially the balls engine — is super-fast, and kick starts a chain reaction that produces explosiveness off the clubface. The revolutionary HEX rodynamics on the cover also are improved, with the hexagons and pentagons optimized to reduce drag, increase lift and maximize distance.