Fixed sides with central division, to take 12, 1829 x 1219 x 25mm (6′ x 4′ x 1”) rigid lightweight or superlight blend type mats only. 3” diameter, rubber tyred, nylon wheels. It is best to move the mats around by trolley. Avoid bending and pulling mats around by their corners. Most damage occurs during handling and transportation so care here will prolong the life of the mats.