Bowling Balls in the High Performance Category are made of a Urethane material. All of the bowling balls in this category have a reactive resin additive in the Urethane. These bowling balls are designed for the following: Upgrade from entry/value category, Symmetric & Asymmetric Cores, Medium to Heavy Hook Potential, Medium to Faster Ball Speeds, Medium to Heavy Oil Conditions, Lower Rev Rates. These balls also have the latest technology available. All balls have a 1 year manufacturer warranty.