Instead of having four legs, this desk chair has a sled base that’s not flat. We took our son to college recently, and found these in the dorm rooms.
The angled base allows the sitter to lean back, but it stops the chair from going too far back. It’s like a two-position rocking chair.Legs are subject to damage when a chair is tipped, but this avoids that problem.
I’ll have to ask how comfortable it is.