The Rattler NU takes advantage of the new chemistry in cover stocks Not Urethane (NU). This chemistry allows Radical to create a unique urethane motion without the pitfalls of a urethane ball. The Rattler NU features the original Rattler core with an RG of 2.480 and a differential of 0.035, giving you a medium DIFF core and a unique cover. The Rattler NU is a great addition to the Rattler lineup, yielding a smooth, controllable, continuous ball motion that allows you to control the backend of the lane.