- 1). Look at the center of the typewriter above the keyboard. It should say "Royal" there. If it does not then it is not a Royal typewriter. The older models are imprinted behind where you insert the paper in the center, instead of behind the keyboard.
- 2). Turn over the typewriter. Look for a serial number imprinted on the base of typewriter.
- 3). Look for the serial numbers 165885-5, X277685, P208665, P249446, 14-1582337, E5903, ES19889, J28077, J30689, BJ63590, S-1635451, O-605667, A569018, KHM-2040988, KMM-2627222, CD-163697, C-1127797R or A-1739469 which are all pre-1950s models. Also look for serial numbers AG-2350325, RA-2672840, HHE-5259197, HHE-13-4912881, B3473176, S3836301, 2A4247769, m5200435, FPCS-7034720, E05121069, MCE 11-8109527, 6418099, SA5390535, CM6303616, MC2876777, MR 8261299 or SB 9028673 which are all models manufactured after 1950.
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