This plastic cover shielded the dual lenses of the 35mm lunar stereo camera that was used to take pairs of close-up photographs of the lunar surface. The cover was removed before the camera’s base was placed on the Moon's surface and the trigger under the handle pulled. The camera would photograph the area beneath its lenses. The resulting photographs would give a three dimensional or stereoscopic effect when placed in a special viewer.
NASA transferred this lens cover to the Smithsonian in 1971.
Transferred from NASA - Manned Spacecraft Center