Pallet Racking Add-On Bay. An add-on bay with an overall size of 4877mmH x 838mmD x 3900mmW. It includes a single upright (4877mm x 838mm) and 4 beams (3810mm x 140mm). This add-on bay will fit a complete bay 838mm deep. When installed onto your existing complete bay It has a 2454kg load capacity per level with a maximum bay load of 9000kg.