Holman Double ProStow Shelf w/ Legs 4 Shelves Sliding Model 48042SPHolman Double ProStow Shelf w Legs 4 Shelves Sliding Model 48042SP The Holman ProStow shelving system is designed to organize and access Milwaukee Packout Storage System within a van. With space for up to eight Packout boxes, this kit provides easy and ergonomic access to each unit. Features and Benefits: Easy access to each Packout unit without having to unstack them or remove them from the shelf. 50lbs weight capacity per shelf. Adjustable shelving