A, High-back swivel chair B, Built-In Lumbar Support C, Spring Tilt Control Mechanism D, Pneumatic seat height adjustment Black LeatherPlus Executive Chair1, High-back leather swivel chair.2, Pneumatic seat-height adjustment, 360-degree swivel3, Ergonomic office chair with lumbar support.4, Heavy duty angled chromed finshed base5, Oversized Dual Wheel Carpet Casters