Storm Rocket Bowling Ball As Storm's original top performance line, Thunder line balls utilize core technology proven effective for years. The countdown is on as the new Rocket prepares to take your game into orbit with its all-new Booster core. Featuring the celebrated R2S coverstock that made the Hy-Road series one of our all-time best sellers, the Rocket is the ultimate all-around, go-to ball. It's 1,500-grit hybrid surface will power through the backend as its Booster core provides the rotation and thrust to launch through the pins. Perfect as a primary ball or as a step-down from our premier or master lines once the lanes begin to transition, no bag is complete without a Rocket. Coverstock: R2S Hybrid Reactive Weight Block: Modified Centripetal Core Factory Finish: 1500 Grit Polished Flare Potential: High Radius of Gyration (RG): 2.54 Differential (Diff): .046 Fragrance: Citrus Grove