What you see is a light linen canvas: an irregular weave, colour that varies across the width, the sort of surface that looks handled rather than manufactured. The unevenness is the design. Formafantasma worked it so that no two stretches of the wall are quite identical, which is the opposite of what wallcovering usually sets out to do.
It is cloth on a nonwoven ground, sold by the metre at 140 cm wide, in two colourways. Certified to EN 13501-1, ASTM E-84 and IMO 5, and tested to EN 12149. Made in Italy. It does well where a painted wall would be too flat and a pattern too much: behind furniture, in a bedroom, along a landing.
