The flexi disc (also known as a phonosheet or soundsheet) is a phonograph record made of a thin, flexible vinyl sheet with a molded-in spiral stylus groove, and is designed to be playable on a normal phonograph turntable. Flexible records were commercially introduced as the Eva-tone Soundsheet in 1960, but were previously available in the Soviet Union as "roentgenizdat", "bones" or "ribs", underground samizdat recordings on x-ray film.
Before the advent of the compact disc, flexi discs were sometimes used as a means to include sound with printed material such as magazines and music instruction books. For this reason, most flexi discs had a spot on the face of the disc for a coin, or other small, flat, weighted object to increase the friction with the turntable surface and enforce consistent rotation. If the turntable's surface is not completely flat, it is recommended that the flexi disc be placed on top of a full sized record.<ref... Read More