The warehouse is located in a spacious hall. After the extension, it will be divided into four floors, with each floor consisting of a matrix structure of ca. 10 aisles and four cross-aisles. All items are stored in uniform boxes that can be easily handled by a human picker. However, the company is planning to apply a couple of different box sizes in the future to better match the characteristics of different items. The total number of storage places approaches 105, while the number of different items stored is expected to increase to 5000 in the future. The stock held of a given item occupies 1–100 storage places, but only a single oldest box is opened for picking. Therefore, stock splitting is not applicable.