Nucleus work chair brings a clean, slender profile to office seating without sacrificing comfort. An advanced suspension material called ilira-stretch NRAM forms the internal back structure, delivering immediate, supportive comfort without the bulk. The cushioned seat distributes your weight evenly to minimize pressure points for improved circulation and reduced muscle fatigue. With the multidirectional stretch of ilira-stretch M4, the back flexes four ways to put instant lumbar support right where you need it. Chair functions include pneumatic seat-height adjustment from 17" to 21-1/2", seat-glide mechanism, 360-degree swivel and dual-action synchro-tilt. Work chair supports users up to 300 lb. Seat size is 20" wide x 20" deep. Usable seat depth is 16-1/2" to 19". Back measures 19-1/4" wide x 25-1/4" high. Distance between arms is 17" to 20". Work chair meets or exceeds applicable ANSI/BIFMA standards.