Nixie tubes such as these ones were used extensively as numeric displays in electronic instruments and computer equipment until they were supplanted by vacuum fluorescent and LED technologies in the mid- 1970s. They were invented at Burroughs. More elaborate Nixie-style tubes (ones with n segments) could display alphnumeric characters and a few speacial symbols as well. The term "Nixie" grew out of an internal Burroughs name for the tube, the "Numeric Indicator X (or ten)," abbreviatred to "NIX tube" and eventually to "Nixie." Donor note: "The 'Nixie' display design originated in 1929 by a Chicago inventor named Henninger. At first, such tubes were custom-made for use as advertising signs. A few early gas-discharge display tubes using the stacked-cathode system were made by National Union and Telefunken prior to 1945. The specific design used in the mass-produced Nixie tubes was developed around 1948 by the Haydu brothers, who sold the patent to Burroughs in 1952. The Nixie (which got its name from a comment written on a mechanical drawing by a Burroughs draftsman, who called it the NIX-1 device) was the most widely manufactured and used numeric display during the 1955-1970 period. Nixies were found in 90% of early frequency counters, digital voltmeters and other digital-display instruments, as well as in computer panel displays and many electronic desk calculators of the 1960s." This item displays: '+/-'.