Rage Fitness Steel Plyo Boxes Solid platform constructed of heavy Gauge tubular steel, 3/4" plywood surface and 1/4" rubber top Easily "nests" for storage to maximize space Recommended for plyometric routines, box jumps, agility and stamina training workouts Built to withstand extreme conditions for ultimate durability Available in 7 sizes: 12", 18" 24", 30", 36", 42"