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. Get pinpoint accuracy and show your style. Available in attractive colors and patterns at an affordable price. Bullet Core Small-shaped version of the high-tech, two-piece. CORE TYPE: Bullet, COVERSTOCK: Polyester, FINISHING STEPS: High-Gloss Polish, WEIGHTS: 8-16 Pounds, RG MAX: 2.715, RG MIN: 2.696, RG DIFFERENTIAL: 0.019, BRAND: Brunswick, BALL PERFORMANCE LEVEL: Entry Performance, BALL LANE CONDITIONS: Dry, BALL COVERSTOCK: Plastic, BALL WEIGHT: 6LB, 8LB, 10LB, 12LB, 14LB, 15LB