The ASICS® GEL-Kinsei™ 4 is a moderate, neutral running shoe designed for daily training and high mileage. Heel Clutching System uses an exoskeletal structure that wraps the heel for a secure fit. Cuprothermo metallic film retains heat in cold weather to keep feet warm and dissipates heat in warm weather to keep feet cool. Biomorphic Fit® provides superior fit and function. Open mesh helps keep feet cool. PHF™ (Personalized Heel Fit) memory foam lined heel collar molds to the heel for a snug, comfortable fit. Asymmetrical Lacing Design better follows the shape of the foot for an improved fit. Solyte™ midsole with GEL® Cushioning System enhances shock attenuation and allows for improved toe off position. Guidance Line is a vertical flex groove in the forefoot for improved gait efficiency. Propulsion Trusstic System® utilizes a thermal plastic unit that connects the lateral heel to the medial forefoot. This unit works to release stored energy and propel you forward during toe-off. Impact Guidance System (IGS®) design creates a smooth and balanced heel-to-toe transition. ASICS® High Abrasion Rubber (AHAR®) in the heel is made of carbon rubber for exceptional durability. DuraSponge in the forefoot is made from a blown AHAR compound, for responsive cushioning and flexibility. DuoSole® outsole provides lightweight, flexible, and durable traction. Removable insole. Wt. 11.9 oz.