The Hammer Effect Bowling Ball is a high-performance ten-pin bowling ball made of reactive resin material with an asymmetrical core type. It is designed for heavy lane conditions and features a sanded finish. This multicolor ball weighs 15 lbs and comes undrilled. Manufactured in Mexico, it is part of the Hammer brand and model Effect. Ideal for serious bowlers, this ball promises an impressive performance on the lanes. I weighted this ball in a cardboard box so take off about 5-6 ounces