This bowling ball ships UNDRILLED with no holes unless you add drilling services. Our beloved Tropical line has evolved again! The all-new Surge Core, with a boosted differential paired with our dependable Reactor formula will give you the curve you've been craving for. Six exciting colors and fragrances will appeal to just about anybody. Coverstock Type: Pearl Reactive Core Type: Symmetrical Recommended Lane Conditions: Dry to Medium Dry Lanes Reaction Type: Slightly Angular Backend Motion on Drier Lane Conditions X Factor Hook Rating Scale (1-20): 11 Radius of Gyration (RG): 2.58 (15lb) Differential (DIFF): .024 (15lb) Flare Potential: 2-4 Medium Core: Surge Coverstock: Reactor Pearl Reactive Factory Finish: 1500 Grit Polished Color: Midnight Black Fragrance: Amrosia Performance: Value Performance