This is a SHARP pocket computer, likely manufactured around 1990. It can be used for learning BASIC programming, as well as a scientific calculator. This item has been internally cleaned and upgraded with an internal RAM expansion to 128KB. Simple calculations and program creation have been performed, and it has been confirmed that calculations and display work without issue, but not all functions have been tested. The exterior has minor scratches and dirt. Please check the photos for details on the condition. ・Regarding the 128KB RAM CARD This item includes a self-made RAM CARD. Programs can be backed up independently using the internal battery. It has been confirmed that the PC-1480U recognizes 128KB, but it does not seem possible to integrate it with the main unit's RAM.