The york sts stackable plyometric box double set have many uses and height options in particular you can use the plyometric boxes for explosive training and step up boxes for all over body conditioning circuit based training key features of the york sts stackable plyometric box double set set includes 2 x 3 inch76mm stackable plyo box 2 x 6 inch152mm stackable plyo box 2 x 12 inch304mm stackable plyo box 12mm high density rubber is used to cover the top of the boxes which generates a