Dezeen's A-Zdvent calendar is back for another year! For 2014, we're bringing you an iconic chair design every day in the run up to Christmas – starting with A: the Air-Chair by Jasper Morrison.

The British designer's 1999 lightweight stackable seat for Magis is made in one piece of injection-moulded polypropylene.

In his book 21st Century Design, Dezeen editor-in-chief Marcus Fairs described the Air-Chair as a "simple yet technologically advanced product."

"The design exploits a technology that was relatively new when the chair launched called gas-injection moulding, in which inert gas is pumped into the hollow centres of still-molten plastic inside the mould, creating enough pressure to ensure the plastic does not shrink away from the mould's surface," explained Fairs.

This technique makes it possible to create complicated forms economically, requiring less material and time to produce, meaning the chairs are more affordable than most "designer" furniture.

The first single-piece Air-Chair was produced in 1999 . A second version consisting of three parts joined by pivoting pins was released in 2001.

"A disciple of the simple, elegantly function approach of 20th century pioneers such as Dieter Rams, Morrison pairs down his designs to the minimum, yet consistently manages to produce timeless, iconic forms," said Fairs.