FringeSport Traditional Wood Plyometric Box/Built or Kit/Jump Training & Conditioning $104.00 Each side is screwed together (if purchased Assembled) – Makes the box infinitely stronger and more durable than just screws. You can buy and assemble them at home – this product can effortlessly be put together with the hardware provided and a handheld power drill. 3/4″ Birch Plywood – This wood is strong enough to handle any size person that can get onto it.