Just a heads up to the do it yourselfers that are building campers if you want to build a colapsable lay flat staircase that doesnt weigh a ton HARBOUR FREIGHT has a set of 1000 lb 84in steel ramps you can cut up for step treads and if you cut them that you keep a 1inch or so tab on each corner to bend around to put a 2in by 10 in piece on each end to either weld to or bolt to then lay your treads out on the floor with 2 sticks of 3/4 or 1in sq tubeing and to make the legs that will let the treads hinge on you can look at my staircase pictures to get it in your head im fixing to get these super heavy treads off mine and replace with these ramps i just stumbled on and they were only 69 bucks