This bowling ball ships PRE-DRILLED. There are 5 sizes and the sizes that we drill are based on the weight of the ball. X-Small: 6lbs- Ages 8 and under, Small: 8lbs and 9lbs- Ages 8-11 and womens ring size from 8-11, Medium: 10lbs, 11lbs, and 12lbs, Ages 11-15 and Adult Ring size 10 or lower, Large: 13lbs and 14lbs, Mens ring size 10-12 or people with larger hands, X-Large: 15lbs and 16lbs, Mens ring size over 13 or people with extremely large hands. If you would like a different size drilled for the weight you selected, you must contact us via email as soon as your order is placed with your order number. Pre-Drilled bowling balls cannot be returned or exchanged. Experience unprecedented power with the Ion Max! A step up in power from the iconic Ion Pro, the Ion Max takes performance to the next level on heavy oil patterns with over 50% more flare potential. Its cutting-edge Element Max A.I. Core, featuring an added weighted disk, delivers unmatched torque and control. The NRG™ Solid coverstock ensures a strong, consistent reaction, while the eye-catching design in bold, contrasting colors makes a statement on the lanes. With the massive ellipse and low RG asymmetrical design of the Element Max weight block, you’re looking at one of Storm's most groundbreaking innovations. Gear up with the Ion Series and dominate all season long! Coverstock: MRG Solid Reactive Weight Block: Element Max A.I. Core Factory Finish: 2000 Grit Abralon Color: Neon Pink/Indigo/White Flare Potential: High Fragrance: Strawberry Milkshake Weight: 12-16 LBS