Shoe of choice for touring pro Agnieszka Radwanska, the Raptor Ultra IV Speed brings together new levels of performance, comfort and stability for the ultimate on court experience. This update from Lotto features the Syn-Pulse cushioning system in the midsole that helps with explosive movement on the court combined with a slightly concave shaped outsole known as the ReactiveArch. The Reactive Insole ridges are positioned in such a way to aid circulation and the absorption of lactic acid. Backed by a 6 month outsole durability guarantee, the outsole of this shoe is made of durable rubber with an open herringbone pattern. This durable shoe will be sure to enhance any player's game with the comfort and stability that it provides.