Aptly named, this rack is super-heavy duty ... have never found a shelving unit that comes anywhere close to the size, strength, or capacity of this one. The unit is easy to assemble; no tools required.  Assembly is a breeze with the assistance of a second person to steady and align the rails. This is a well-engineered, well-manufactured product.  We assembled the unit in the basement to hold storage bins; it's great to have them off the floor.  The rack would also work well in an oversized garage or workshop.  It would be a real challenge to overload this rack.  Highly recommended.