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. BEHIND THE DESIGN: There's no better time than right now to reignite those beloved memories of the late 2000's legend the CELL that put Roto Grip back on the proverbial map. X-CELL is our way of paying homage by blending the original look with our modern day core and cover technology to give players even more forgiveness and versatility than the original everyone loved. On the inside you will find the original Nucleus block wrapped in one of the greatest inventions since sliced bread, A.I. Core Technology. This core allows for greater energy dispersement from the center to the cover to increase overall pin carry. While on the outside you will find our brand new ULTRA versatile, ULTRA responsive - eTrax ULTRA Solid Reactive coverstock that features chemical enhancements mixed into the material to provide an ULTRA consistent reaction shot after shot PRODUCT DETAILS: COVERSTOCK: eTrax ULTRA Solid Reactive CORE: Nucleus A.I. Core COLOR: Turquoise / Navy / Black FINISH: 2000 Abralon CONDITION: Medium - Medium/Heavy Oil FLARE POTENTIAL: High AVAILABLE WEIGHTS: 16 – 12 lbs. RG: 16lbs(2.50) 15lbs(2.50) 14lbs(2.55) 13lbs(2.56) 12lbs(2.58) Diff: 16lbs(.050) 15lbs(.056) 14lbs(.048) 13lbs(.034) 12lbs(.031) Int Diff: 16lbs(.018) 15lbs(.019) 14lbs(.016) 13lbs(.011) 12lbs(.009)