Base diameter Weight Available colors: Blueberry, Clay, Moss, Rosehip, White, Black, Grey, Sand. Available accessories: Piston h.150mm/h.265mm, footrest ring, padded cushion for seat The OK seat is an ergonomic plastic chair with a small cushion integrated into the seat for greater comfort. The saddle seat can be adjusted in height and depth between low and high working positions, up to the standing position, allowing you to be more dynamic in your movements. The height-adjustable backrest with integrated armrests facilitates both desk work and upper body rest. There is also the possibility to adjust and lock the backrest tilt tension. Warranty: 10 years from the date of production on any part of the chair, on any manufacturing defect. Certifications: OK is certified according to EN 1335, EN 16139, ANSI / BIFMA X5.1, GS Mark standards. In Italy it is certified as conforming to the ergonomic standard of seats for video terminals issued by Ergocert. Environmental certifications: Environmental product declaration (EPD), GREENGUARD certification, Möbelfakta certification