【Ergonomic Office Chair】SIHOO M102C computer chair offers proper support for your head, back, hips, arms, and waist. It allows easy adjustments for seat height, headrest, lumbar support, and flip-up armrests, suitable for scenarios like work, relaxation, study, entertainment, and extended sitting. 【Modular Adaptive Lumbar System】 This office chair's premium mesh lower back support enhances airflow and thermal management while delivering pinpoint pressure alleviation to the waist area. Its 6cm (2.36") vertical adaptability enables personalized comfort configurations, even during marathon work sessions. 【Configurable Pivoting Arm Supports】 The generously proportioned office chair incorporates multi-directional armrests capable of forward-backward sliding and lateral rotation, providing optimal forearm and elbow bracing during tasks. The space-efficient design permits seamless storage beneath work surfaces. 【Reinforced Expanded Cushioning】 Our ergonomic seating solution accommodates weights up to 300lbs (136kg) through its widened, deepened construction—exceptionally suited for varied physiques and an optimal choice as a tall-person office chair. High-density foam minimizes gluteal and coccyx compression for sustained sitting comfort. 【Simplified Setup, 36-Month Coverage, 30-Day Value Guarantee】 SIHOO champions premium customer care. The M102C holds TÜV certification and complies with US SGS BIFMA endurance and safety benchmarks. Includes complimentary component replacement during warranty plus expedited issue resolution within 30 days. Reach out for outstanding assistance.