Texas Instruments calculator TI-53 Constant Memory 1980 Italy

From Texas Instruments from the 1980’s, the inventor of the handheld calculator in 1967, come this TI-53 LCD with constant memory which was made in Italy. It is clean and in working condition but it has unresponsive keys and it is an overall very slow machine (no batteries included). It comes with the original black plastic case, which is also in good condition. It measures ca. 13 cm or 5 1/4  inches tall. There are only small signs of use. Selling as a cool desk display piece since it is not very usable (priced accordingly). Do check the attached video to learn all about the history of the calculator.