Alera ST42LS30B Stratus Series Leather Mid-Back Swivel/Tilt Chair, Burgundy Deep cushioned back and seat conform to body contours for proper alignment. Curved polyurethane loop arms are soft, yet durable. Seat height adjusts to accommodate different users comfort levels. Five-star base with hooded casters. (alternative casters are available) Alternative casters are available to meet your specific needs.