This is a CASIO calculator, likely from the 1970s. It features green illuminated numbers and a metallic surface. It operates on four AA batteries. The case has been lightly cleaned, and the buttons and display have been confirmed to function with basic calculations. The display may flicker during calculations, which is a normal characteristic. The body has minor scratches and dirt. Please check the photos for the appearance. ※The ruler in the photos is not included. ※Batteries, cover, and instruction manual are not included.