NEVER Opened Aeron Chair. Aeron Chair Frame / Base: Graphite / Graphite Size: Size B – Medium Back Support: Adjustable Posturefit SL Tilt: Tilt Limiter and Seat Angle Arms: Fully Adjustable Arms Armpad: Standard Caster: Multi-Surface Caster with Quiet Roll. Seat Depth17 inchesSeat Height21 InchesItem Weight50 PoundsUnit Count1.0 CountItem Dimensions D x W x H16″D x 25.75″W x 34.25HSizeSize B (Medium). Maximum Weight Recommendation300 Pounds.