Love the stopper mechanism that was integrated into the housing of the roller system. Rotate the red disc to lower or to raise the stopper or even to elevate and level the desk. Its easy and highly adjustable.I would love to see a better packaged box for these set of rollers.. The current ones are flimsy and are torn upon arrival. Why am I complaining? Because I bought one set to try and loved it so much and bought the second. Both times, the boxes came torn and mangled. But the rollers survive!
Chris 
