Underwood Sundstrand 8120P Adding Machine

This ten-key printing electric adding machine has a gray metal case with ten white plastic number keys arranged in a block. Left of the number keys are CORRECTION, B’K (/) SPACE, and REPEAT keys. Right of the number keys are SUB- (/) TRACT, ADD and N.ADD (/) TOTAL keys. Above the keyboard is a place indicator for up to eight places, which moves from left to right as up to eight digits are entered. The 2-3/8” (6 cm.) paper tape is in the back, A black ribbon is underneath a metal plate held down by thumbscrews. The machine prints up to eight digits, and the rightmost type bar prints symbols. One lever on the top right releases the position of the carriage and the second releases tension on the platen. The motor is on the left.
Gustav David Sundstrand, the son of Swedish immigrants to the United States and a resident of Rockford, Illinois, applied for a patent for an adding machine in 1912, and was granted it in 1920 (U.S. Patent 1,329,028). He applied for a second patent in 1914, which was granted in 1916 (U.S. Patent 1,198,487). The Sundstrand originally was produced by the Rockford Milling Machine Company - by 1920 it was a product of Sundstrand Corporation, a closely related firm. Oscar Sundstrand, a brother of Gustav David, took over primary responsibility in improvements in the adding machine. During the 1920s, several business machine companies consolidated. The Elliott-Fisher Company acquired rights to the Sundstrand adding machine in 1926, and soon merged with the Underwood Typewriter Company. Hence the adding machine was renamed the Underwood Sundstrand.
This example is from considerably later in the history of the machine. The “8” in the model number indicates that the machine has a capacity of listing eight-digit totals, while the “P” signifies a portable electric machine with “Multiflex” control, allowing more rapid repeat addition and subtraction. According to the accession file, the donor acquired this machine secondhand in about 1953.
American Office Machines Research Service, III.
Fédération Nationale des Chambres Syndicales de la Mécanographie, Fédération de Reprise officielle des Machines à Ecrire, Machines à Calculer . . ., Lyon, 1970, p. 86.
Underwood Sundstrand, “Underwood Sundstrand presents the right machine with the right keyboard . . . The only complete line of ten key adding machines,” [no date], 1990.3188.07.
Currently not on view
Object Name
adding machine
date made
Underwood Elliot Fisher Company
Physical Description
metal (overall material)
paper (overall material)
plastic (overall material)
overall: 28 cm x 32.5 cm x 38 cm; 11 1/32 in x 12 25/32 in x 14 31/32 in
place made
United States: Connecticut, Bridgeport
ID Number
maker number
accession number
catalog number
Science & Mathematics
Adding Machines
See more items in
Medicine and Science: Mathematics
Adding Machines
Data Source
National Museum of American History, Kenneth E. Behring Center
Credit Line
Gift of Harry Schneider
Additional Media

Visitor Comments

Add a comment about this object

**Please read before submitting the form**

Have a comment or question about this object to share with the community? Please use the form below. Selected comments will appear on this page and may receive a museum response (but we can't promise). Please note that we generally cannot answer questions about the history, rarity, or value of your personal artifacts.

Have a question about anything else, or would you prefer a personal response? Please visit our FAQ or contact page.

Personal information will not be shared or result in unsolicited e-mail. See our privacy policy.

Enter the characters shown in the image.