A sculptural seat with a pure and rationalist form, this chair became an authentic Manifesto for Neoplasticism, embraced by the Dutch De Stijl movement in 1917. An outlook shared by Piet Mondrian, whose objective was to seek out the essential nature of things, combined with the harmonious equivalence of colours, and the use of right-angle. Rietveld produced his first prototypes in 1918, expressing the philosophy of organising space using the same colours for similar components. He later applied this same approach to separate out constructional elements according to their function. Thus the base was black, and the seats coloured. As a consequence, the name of the piece changed, from Slat Chair to Red and Blue.Seat/Backrest Birch plywood panel with beech veneered edges and tops.Finishing polyester lacquer, halfpolished, in blue (seat) and red (backrest).Structure Massive beech wood. Finishing matt black lacquered, with crossbar edges in yellow or in white.The construction system of the frame of the chair is based exclusively on a sequence of joints and wooden pins.