An integrally formed base arrangement of an office chair, and more particularly, a base arrangement integrally made by plastic material, comprising: a) a middle axle seat; b) a first U-shaped pivotal seat perpendicular to the middle axle seat; c) a claw member having a plurality of arched supporting...http://www.google.com.au/patents/US7887138?utm_source=gb-gplus-sharePatent US7887138 - Integrally formed base arrangement of an office chair
