Three vintage stereo viewers, each varying in design and material. The black viewer features a sliding mechanism for viewing and includes red and silver adjustment controls. The swirled marbled viewer is crafted in a black and white finish with a curved top design. The cream and brown viewer is made of plastic and comes with its original yellow and blue Arcadia-branded box. One viewer measures 7 inches high, 4 inches wide, and 2 inches deep. These devices were popular for viewing stereoscopic images, creating a three-dimensional effect.