This unique Circular Step Ladder is commonly called Library Stairs or Library Ladder. The Library Stairs pictured is made from Jatoba which is a South American Locust Tree. The center pole provides a means to steady yourself as you climb the stairs. It also doubles as a handle to move the Library Stairs from bookcase to bookcase. The treads are slightly crowned, which allows the user to subconsciously keep their feet in the center of the tread.
I have made many of these Library Stairs some with as few as three treads and one with six. Each tread gives the user an additional 8" in reach. The four step model is the most popular giving the user an additional 32 in reach. I can make one for you from any hardwood from Alder to Zebrawood. Prices will vary depending on the wood and the number of steps.