The Nike Lunar Tri+ training shoe features evolved Flywire technology that hugs the entire length of the foot with customizable lightweight support. Heel clip engages upon footstrike to provide a snug fit and support. Encapsulated Nike Zoom unit adds first step responsiveness. Rubber outsole with natural-motion-engineered flex grooves promote a stable platform. A combination herringbone Waffle pattern gives multi-surface traction. Wt. 12.6 oz.