Bring more fear to your competition with the Hammer Fierce Phobia bowling ball. The Fierce Phobia is part of Hammer's upper-mid performance line which includes their legendary Black Widow bowling balls. This ball uses the symmetric Phobia core and combines it with the successful Semtex coverstock in the hybrid version to cover this ball and generate an aggressive mid lane and backend motion. This bowling ball is Carbon Fiber Infused! Carbon fiber is one of the toughest materials on earth. Hammer decided to add this material to the inner core of this ball for added strength and durability allowing them to offer an incredible 3 year warranty.