With the kneeling stool, your center of gravity is shifted by easing your hips forward as you kneel, correctly aligning your back, shoulders, and neck to reduce spinal stress by as much as 50% over normal chairs. Moving the hips forward distributes body weight better for more ergonomic posture that relieves strain on lumbar muscle groups and eliminates the pain of sitting for long periods of time. The knee pads and seat are Tempur-Foam (used in sleep surfaces of NASA spacecraft), renowned for its ability to mold and conform to the individual body shape of the sitter for comfort without pressure points. The foam springs back to its original shape almost immediately after the sitter rises, so it will not lose its resilience or cushioning even after years of daily use. The seat height is adjustable and the stool rolls smoothly and quietly on four nylon casters. The sturdy wood frame supports up to 250 lbs. Tools for minor assembly are included. Black. 24 H x 18 W x 21 D. (22 lbs.) Express and Premium Delivery not available for this item.