XTC Mesh ThunderX3 Ergonomic Chair: Designed for all-day comfort and ergonomics Dimensions: General (W x D x H): 68 x 70 x 118-126 cm; Seat (W x D x H x H): 51 cm x 52-57 cm x 16cm x 48-56 cm With BIFMA X5.1 approved Class 4 gas piston/lift, XTC has a maximum recommended weight of 275 lbs SYNC5 Multifunctional mechanism with 5 adjustment functions for better adapting to user needs: height, depth, angle, resistance and tilt. Completely adjustable: adjust height (8cm), seat depth (front and back), headrest (bidirectional), lumbar support (self-adjusting), armrests (height, forward/back and inside/outside angle) and backrest (90° to 135° tilt)