School Classroom Training Office Chair with Writing Board Chair Hall Basic Customization. Customizable Design: Back, seat, leg, and size can be customized to specific requirements. Ergonomic Lumbar Support: Features elastic adaptive fixed lumbar support for comfort. Silent Anti-Vibration Wheels: Equipped with 60mm luxury silent anti-vibration castors. Durable Steel Base: Constructed with 350 square steel tube base for stability. Long Warranty Period: Provides 3 to 5 years of warranty coverage. High Production Capacity: Supply ability of 50,000 pieces per month. OEM and ODM Services: Offers both OEM and ODM customization services.