... :industry ladder(straight ladder,extension ladder,combination ladder)1x6,1x7…1x14 straight ladder2x6,2x7…2x14 extension ladder3x6,3x7…3x14 combination ladder6:household ladder(aluminium step ladder)2,3 ... (we can add wheels and handrail)8:step ladder(steel step ladder)2.3.4.5 steps steel ladder,different type9:work platform10:platform,workshelf,hinge ...