The human spine has a natural curve which is known as it's lordosis.

When you sit on an Opus Stool your pelvis is tilted at the correct angle which allows the spine to assume it's natural lordosis. Sitting this way can help to prevent backache and ease existing pain caused by poor posture.

Circulation in the legs is unimpeded and weight is relieved from the knees making Opus the most comfortable way to kneel on the floor.