QTZ80 tower crane model 5612, self-erecting construction6t topkit tower crane, hammer head type, max load 6t, standard mast section 1.835m*1.835m*2.5m. the main limb material square tube 135*12mm Manganese steel. it is applicable for Building height up to 50 floors (151.2m), loading capacity up to 6t, jib length is 56m.