This model was first placed on the market in 1912; production ceased when the Corona plant was retooled for War efforts in 1941 with machine 700354. The chief differences between it and later models are that it has a 3-bank, double shift keyboard, and it folds. It is low in design when folded, being 3-7/8 inches, and 6-3/4 inches when opened.
The regular model has 28 full size keys and the X-C amd XC-D models have 30 full sized keys, The X-C may have any one of four keys may be made dead, while the XC-D has all four keys dead. All keys have the standard distance between each, making this model suitable interchangeably with standard office typewriters once comforatble with the double-shift mechanism. It has a 10-inch carriage, permitting insertion of No. 10 envelopes, and writes a line 8.3 inches long (83 pica spaces); Ball bearing, carriage shift with right and left hand shift keys, left hand line space and carriage return lever, standard 7-yard, 2-color ribbon with automatic and/or manual reverse; variable line spacer on the left side of carriage; and carriage release lever at both ends of carriage. The back-spacer key is situated above and to the right of the keyboard.
Specifications of Folding Models
General Features: Portable size, front stroke, double shift (carriage shift), visible writing. When the machine is to be placed in the case, the carriage folds over on the key board, during which time it is disconnected from the escapement. When folded back the carriage automatically locks itself in operating position.
Keyboard: Three rows. The regular model has 28 keys writing 84 characters; the X-C has 30 keys writing 90 characters; The XC-D model has 30 keys writing 90 characters of which four keys are "dead" (i.e., these four keys are not connected with the spacing mechanism and are used for language accents). Right and left hand shift keys with left hand shift lock and release. Back space key situated above and to right of keyboard.
Carriage: Hinged on two steel arms to allow folding compactly over keyboard when placed in case. mounted on ball bearings and rollers. Takes paper 9-3/4 inches wide with writing line 8.3 inches long. Escapement is dog and rack design with adjustable tension. When folded the escapement is locked out of engagement with rack to prevent damage while machine is in transit. Left hand line space lever with adjustment for single, or double line spacing. Back space mechanism operated from key on keyboard; right and left hand margin stops. The carriage could be build to move from left to right to write Hebrew, Arabic, and such languages on X-C and XC-D machines.
Printing Mechanism: Type bars are flat steel with heels to prevent battering; mounted in solid slotted segment. Type guide at printing point. Two-color, 7 yards long, 1/2-inch ribbon with automatic reverse.
Construction: Stamped aluminum frame, one piece. Size of machine when opened, 9-3/4 x 11-5/8 x 6-3/4 inches; when folded, 9 x 11-5/8 x 3-7/8 inches; outside dimensions of case, 12-1/2 x 10 x 4-5/8 inches. Weight: 9-3/4 pounds with case; 6-3/4 pounds without case. Finish: Black enamel until CORONA began using DuPont DUCO® finishes, later models have crystaline panals that may be colored rose gold or another DUCO®; finish, with nickel trim. Type faces: Pica, elite, medium Roman, billing or italic.