Medium duty.  Goes together with 6mm hex head machine screws.  The allen wrench that was supplied works but does not easily fit into the screws. It would take all day to tighten the screws; so I cut the wrench and installed it in my drill driver.  Worked a lot better and faster.  Table wobbles a little with screws tight. The chair cushion supports are vinyl and will  fail in time.  Should have been metal.