Louden® Stackers, Special Carriers, and Special Track Devices ACCO designs and manufactures stackers, stacker cranes, special carriers, and special track devices, including swing out sections, lift sections, expansion joints, scale sections, etc., to meet the requirements of your material handling needs. STACKERS The first Louden stacker was built back in 1869 and used for storing hay. Today, more than a century later, Louden stackers stack anything from small parts to large bundles of bar stock weighing thousands of pounds. Louden offers material storage systems featuring Louden stackers, Man-Stax manual storage and retrieval, and order picking machines. With a Louden system, movement of all sizes and shapes of material is made easy. Floor space is conserved and material is immediately accessible. Moreover, the equipment can operate in narrow isles, greatly increasing storage capacity and freeing floor space.