The back on this chair runs 28 in, tall enough that a built-in headrest sits where the head actually rests rather than behind the shoulders, and that height is what allows the spine to be supported in one continuous line from lumbar to neck. Below it the seat measures 20 by 18.5 in with a waterfall front edge, the curve that keeps pressure off the underside of the thigh through a long working session. Upholstery is linen fabric rather than coated leather, skin-friendly in direct contact and finished in a two-tone scheme with visible stitching, so it reads as furniture instead of equipment. The armrests flip up through a full 90 degrees. Folded down and soft-padded they carry the elbows; folded up they clear the way for the chair to push under a desk and take up no width at all. Movement is handled by a rocking mechanism with a tension control knob, which allows a dynamic shift of position through the day rather than one locked posture, and that movement is what relieves accumulated fatigue. A height adjustment lever runs the seat between 19 and 23 in on a premium gas cylinder for smooth, safe lifting. Underneath, a 5-claw metal base provides stable support and smooth-rolling PU casters handle mobility. The chair is 27.5 by 27.5 in across and 45 to 49 in tall, with armrests 27 in wide, rated to 275 lbs and weighing 33.5 lbs on the scale. Assembly is needed. Specification: Color: White & Black/Gray & Black; Material: Linen Fabric Metal Sponge; Overall Dimensions: 27.5" x 27.5" x 45"-49"; Backrest Height: 28"; Armrest Width: 27"; Seat Dimensions: 20" x 18.5"; Seat Height: 19"-23"; Weight Capacity: 275 lbs; Net Weight: 33.5 lbs; Box Qty: 1; Assembly Required: Yes; Package Includes: 1 x Office Chair 1 x User Manual