The new 2010 4K Pump is perfect for the player who want a lot of performance for little money. The 4k features the PUMP that provides the ultimate level of personalization and comfort by adjusting to an individual’s feet. The tongue in made of a 7MM HIGH-DENSITY FELT that Works with the contours of the foot for added comfort with lace bite protection. Another great feature is the QUICK-DRYING DOUBLE DENSITY MICROFIBER LINER that Ensures comfortable fit while providing added durability.