The Machine Tool Storage Unit Alpha-Four functioned as an orbital storage facility throughout the initial Death Star construction phase. Furthermore, Celot Ratua Dil briefly utilized it as a safe haven as he executed his departure from Despayre. Predominantly, it housed spare components intended for various mechanical instruments employed in the Death Star's creation. The unit also held considerable oxygen and hydrogen gas reservoirs, a storage cabinet containing multiple Vac suits, and a standard maintenance droid secured within a separate container. Luckily, a container of Vulderanian grain flakes was mistakenly left aboard the storage unit, and Ratua leveraged all of these resources to ultimately conceal himself on the Death Star.