Updated ASICS GEL-Challenger 10 tennis shoes now feature the Flexion Fit™ upper, which provides a more form-fitting environment without sacrificing the necessary support for high-performance tennis. With excellent midfoot stability, you'll experience high confidence as you play. Players will enjoy the cushioned feel and comfort during movement.Upper: Flexion Fit™ provides form-fitting comfort without sacrificing support. P.H.F.™ (Personal Heel Fit) system uses two layers of memory foam to line the heel collar and mold to the athlete's heel, creating a personalized fit. Synthetic leather provides lightweight support. Padded tongue and heel collar enhance comfort. Lace-up front offers an adjustable fit. Mesh offers breathable flexibility.Midsole: Rearfoot and forefoot GEL® cushioning systems attenuate shock for added comfort. Solyte® compound is lighter weight than ASICS' standard EVA and SpEVA®. SpEVA® midsole material improves bounce-back characteristics and decreases midsole breakdown. Trusstic System® reduces the weight of the sole unit while retaining the structural integrity of the shoe. Removable sockliner for added comfort.Outsole: AHAR+ blown rubber outsole delivers enhanced cushioning and durability. Non-marking.