These soft plyoboxes are designed to be less intimidating for the developing athlete than steel boxes. Standard 28" x 28" base with 5 different heights available. The 24" high box is built with 1.8 lb. density polyethylene foam which provides stability, shock attenuation, and performance. Box is secured for stacking with industrial strength Velcro and has a durable vinyl cover.Weighs less than 28 lbs. and has two reinforced handles for portability.