In 1951, the 23-year-old Kjærholm completed his first chair that would go into production: the PK25. The chair's frame is constructed using only one piece of steel and the seat is made from flag rope. This began the designer's obsession with just focusing on the essentials to engineer his concepts into reality. The PK25 is bent from cuts made into the metal and the rope is woven very tight to provide support.  Photo 3 of 11 in 10 Things You Didn't Know About Poul Kjærholm