Photograph of the flight-hardware instrument cavity (to be compared with Fig. B.1). Evident are the large amounts of MLI, specifically the carbon-charged black Kapton that shield NISP (lower right) and numerous structural components. The orange-brown anti-static tapes are made from uncoated Kapton and are omnipresent. Kapton and MLI form primary water reservoirs. A high-resolution image is available at https://sci.esa.int/web/euclid/-/the-euclid-payload-module. Copyright: Airbus Defence and Space - Toulouse.