Extremely durable and well made. Be sure to order the largest of the three listed. The other two are small rings that can be tightened with a finger. Of course, only the large square is shown, so you might think you're ordering a smaller version of the full pen. My task is to open a hatch in the basement in a hard wooden floor (there are hydraulic elevators for this). no screws, but most hardware stores have chrome or stainless screws that will do for four for less than a dollar. Two photos are added later to answer a question from someone asking about the door itself.