Breathable mesh spans the whole back here, and behind it sits a lumbar pad measuring 16.5 by 10.5 inches that pushes into the lower spine instead of leaving a gap. The headrest slides 3 inches to meet taller and shorter users, while the backrest swings back through 45 degrees for a break from the screen. Armrests do three things at once: flip up 90 degrees so the chair slides under a 20-inch gap, shift 2 inches forward and back, and rotate 45 degrees to line up with the forearms. Under the mesh, elastic sponge keeps pressure off the hips without bulk. Seat height covers 18.5 to 22 inches, the frame handles 300 lbs, and the whole chair weighs 26.5 lbs at 25.5 by 25.5 inches with a top height of 49 inches. Flip-up padded armrests let the mesh chair slide beneath a work desk after use. The adjustable headrest and lumbar pad give the sitter separate ways to set upper and lower back support. Net weight: 26.5 lb