Solid Chair ConstructionThis mid-back office chair is constructed of hard-wearing nylon mesh, durable star base, solid rolling casters and SGS-certified gas cylinder. It has passed BIFMA X5.1 Test and is recommended for office use for customers under 100kg. Adjustable Seat HeightThe seat height of this computer mesh chair can be simply adjusted from 35cm/13.8 to 45cm/17.7 by a little push-up/press down at the lever under the seat according to your needs. Star Base & 360 Degrees WheelsTwisting and turning about is integral within the office. So we adopt a stable star base and equip it with 5pcs 360-degree swivel wheels, ensuring fluent and quick movement and keeping up your quick pace of work. - EONLION Black Mesh Office Chair, Swivel Task Chair with Lumbar Support