Orthopaedically designed for sitting comfort Specially re-inforced plastic material used to ensure the correct sitting posture. Hard enough and does not bend due to body weight which maintain correct body ergonomy. Useful in office and where ever long sitting is inevitable. Mainly recommended for High back executive chairs. Gives perfect contour to back due to its extended side wings. The extra lumbar support provided moves up and down to give correct body posture while sitting. Color may vary.