One of our favorite

Dr. YES Stackable Chair, Set of 2 by Kartell

Set of 2 Dr. YES stackable chairs in modified batch-dyed polypropylene.

Colours: Brown, Orange, White, Yellow, Grey, Black, Red
Dimensions (each chair): w 20.5" h 31.5" d 19.7", seat height 18.5"
Weight (each chair): 9.9 lbs
Designer: Philippe Starck with Eugeni Quitllet