The Nike Zoom Rival MD IV is an entry-level track spike designed for the high school athlete competing at 400-1,500 meters. Mesh and synthetic upper with synthetic overlays cradles the foot to provide improved comfort and a secure fit. Thin EVA wedge midsole. Full-length solid rubber outsole with seven removable spikes encased in a nylon plate for optimal traction on many surfaces. 1/4" pyramid spikes. Comes with a wrench. Wt. 7.0 oz.