Keyboard stool easy to install (no need of manual or tool). Its primary function is the foundation for keyboard, it fulfills its role. After unpacking, I was surprised to visually limited depth (24 cm), but it holds up. You have to sit in the middle and not on the edge, otherwise the fall (this is due to the shape of the foot 'X'). This is a very good buy. There are better, but it will be more expensive, and not always justified.