The Pana-Vue 6560 Slide Viewer #1 is a table top viewer that has a two-way base for a choice of viewing angles. It features a bright, 4x magnification on a bright 2.25 x 2.25" viewing screen. The light bar lock provides constant illumination by not having to hold the button. It operates on two "C" batteries (not included) or on household current with optional GAF transformer.