Ergonomic Office Chair with 3D Lumbar Support 3D 360° Rotation Arm and 3D Headrest 135° Stepless Tilt Function Mesh Chairs. 6-Year Free Warranty: Covers chair base, casters, and gas lift with free repair for shipping damage. Customizable Options: Fabric, base, and casters are customizable; OEM/ODM services available. 4D Adjustable Armrests: Equipped with 4D adjustable armrests for personalized ergonomic support. Premium Materials: Constructed with metal frame, polished aluminum alloy base, and breathable mesh. Professional Design Service: In-house design department provides artwork and design before production. Fast Sample Delivery: Samples delivered in 7 days; sample cost refunded upon bulk order payment. Global Certifications: Products certified with CCC, ISO9001, CE, and SGS for quality assurance.