The black single ladder adopt 6063-T5 advanced aviation aluminum alloy,with a hardness of 15 degrees.Aluminum alloy thickness:2.0mm thckness of transverse,1.5mm thickness of round handrail. All size:2.0m,2.6m,2.9m,3.2m,3.8m,4.1m,4.4m,4.6m,5.0m,5.4m,5.8m,6.2m
