These Portable Work Platforms were designed to hold heavy weight. Unlike Scaffolding they are of a rigid nature but provided a simple method for adjusting the height with a forklift. They were designed for large component assembly. The working height of the platform is easily change by holding the weight of the platform with a forklift, pulling spring loaded retainer pins, locking them out then lifting the frames to the desire height and then releasing the pins to re-engage at the desired height. 16 & 18 ft Models were built.