... height C: Extended lengthD: Space between rungsE: Ladder widthF: Width at basefolding aluminum ladder with joint 3 steps Specification: Model#5100151002510035100451005Sec x Rungs ... , stairwell ladder, scaffold, standoff ladder, work platform, and work bench, etc;Compact folding ladders in 4 sections with 6 sturdy locking hinge joints ...