Back by popular demand is the Hammer Purple Pearl Urethane bowling ball. Are you still wanting the ball reaction that dominated bowling in the 80's and 90's? Well, Hammer does and they have brought it back with this mid-performance urethane bowling ball. This ball has modified the popular light bulb core to create the LED core design and covered it with a Urethane Pearl cover and finished it with a 500 grit, then 1000 grit, and then 2000 grit Siaair Micro Pad. This combination offers incredible control the length of the lane on light to medium oil.