MuscleDriver USA Plyo Hurdles are a great portable agility-training implement. Use any combination of heights and positions for jumping in forward, backward, and lateral directions. Use in combination with a MuscleDriver Weight Vest or Shoulder Weight to intensify the workout and build more explosive strength. Each hurdle features a design for easy folding to stack, transport, and store. Sizes are 6", 9", 12", and 18". Made of durable PVC covered in nylon fabric. All sizes have a width of 19 inches.