This chair is made of an aluminum frame for a long-time use and needs no special maintenance. It's lighter than the steel chair and can be moved easily. The ergonomic design with durable Textilene fabric helps reduce muscle tension and stress, providing the perfect balance between hard and soft surfaces for optimal comfort. You can stack chairs on top of the other to save space for unused time. Please NOTE: This set will be separated into 2 boxes for delivery. Because of the timeliness of logistics, their arrival time is different.