The YOYO Chair is a height-adjustable sit-stand chair. The moulded foam seat and back and the nylon base with castors ensure user comfort and easy mobility | Its innovative design and clear simple style make it the perfect addition to the modern office environment | Height-adjustable swivel chair | Backrest & Seat Made With Moulded Foam | Gabriel - Mozart FC3103 Dark Grey Fabric Finish | 323W Wire-Control Height Adjustable Mechanism | XieQiang Gas Lift 200/0, Class 4 | Black Nylon 5 Star Base With Top Grip Treds | 60/25 PU Castors | Backed by a 10 Years warranty