Celluloid sheet, printed in collotype and hand-coloured with stencils, a manual engraving on the surface reproducing the cracks of the original. Unused example that remained with Iliazd after the assembly of the Series C valise boxes.

The Large Glass, or The Bride Stripped Bare by Her Bachelors, Even, is Marcel Duchamp's central work, produced in New York from 1915 to 1923, the date on which he declared it "definitively unfinished". Made on two superimposed glass plates reaching 272.5 cm in height, it has been held at the Philadelphia Museum of Art since 1953. In 1926, while being transported from the Brooklyn Museum, the work was accidentally shattered into numerous fragments; Duchamp, who only discovered the damage in 1931 when opening the crates at Katherine Dreier's, chose to seal the shards between the plates following the existing cracks, thereby integrating the breakage as a constituent element of the work.

It was from 1935 that Duchamp conceived the Boîte-en-valise project, a portable museum bringing together miniaturised reproductions of his entire body of work. The Large Glass is the most ambitious piece to reproduce: it involved reducing a monumental work of 272.5 × 175.8 cm to a format of 37.5 × 23.5 cm, a reduction to roughly one-seventh of the original, while still conveying the chromatic complexity and transparency specific to the glass support. In a letter to Katherine Dreier dated 5 March 1935, Duchamp specifies that he did not want a simple photographic copy but a genuine "interpretation" of the colours: he intended to work the tones himself in order to approximate, on celluloid, the visual effect of the original work. The project ultimately took him four to five years of work, from 1935 to 1940, with constant back-and-forth with the printer.

The reproduction was executed on celluloid using the collotype process, a photomechanical printing technique based on dichromated gelatin that allows a particularly fine rendering of half-tones, comparable, according to Duchamp, to that used for the reproductions of his Green Box of 1934. The sheet was then hand-coloured using stencils, a delicate operation allowing the application of the characteristic flat colours of the bachelors in red-orange and of the Bride in the upper section.

The present example derives its particular historical value from its direct provenance from Iliazd (Ilia Zdanevitch, 1894-1975), the Georgian futurist poet who became a printer and art publisher in Paris, a central figure of the avant-garde, whose collaborators included Picasso, Braque and Miró. It was to Iliazd that Duchamp had entrusted the printing of the celluloids intended for the Series C boxes assembled in Paris in the 1950s. It was during this period, around 1955, that Iliazd carried out the assembly of the boxes in this series; the surplus celluloid sheets, not inserted into the boxes, remained in his possession. The present example is one of these production surpluses: preserved in perfect condition, it was never inserted into a box, making it a document of the first importance on the manufacturing process of the Boîte-en-valise.