Metro HD Super mobile worktable with bottom 3-sided frame. Heavy-duty: HD Super work centers are designed and built for heavy-duty applications. The work surface is made of seamless, 14-gauge stainless steel with an 11-gauge support structure that virtually eliminates any "drumming". Greater rigidity; work centers features 1-5/8-inches diameter HD Super posts and the tapered sleeves and corners of patented Super Erecta Shelf construction. These two features assure a rigid, wobble-free table. Easy to assemble; units are shipped knocked down and can be put together in minutes without special tools. Bottom shelf of frame is adjustable in 2-inches increments. The table top fits over plastic sleeves at the top of the posts.