Black Hammer 2001 sets the standard by which all heavy oil balls will be
judged, with a 2.465 RG and .038 differential, and the most versatile cover
stock introduced to the game - Nylothane. Nylothane is the perfect
combination of particle and reactive urethane, which can easily be polished
or sanded to match the lane condition and the bowler's style. The new
compact, explosive HD core (Heavy Density Core) features the densest
material ever put inside a Hammer bowling ball, with a density of 4.50. The
HD core is so compact and dense most drillings will not even hit the core
leaving the core's integrity intact for optimum striking ability. The
specifications are: Cover stock: Nylothane, matte finish; Core: HD core
(densest material ever put inside a Hammer bowling ball); Hook potential:
overall (20), backend (20); Length: 12; Radius of gyration: 2.465;
Differential: .038; Flare potential: 4-6"; Hardness: 73-74 D Durometer;
Weights: 13-16 lbs.