◆ Casio calculator S-2, over 40 years old ◆ Received from my parent, used until yesterday ◆ I've been using it because its ease of use is unmatched ◆ Operates on 4 AA batteries (I replaced them with new ones, so they should last for over six months) ◆ The rubber on the bottom left is missing, but it didn't affect use. ◆ Sometimes the power doesn't turn on easily, but it works after a few tries. ◆ The numbers are easy to see and it's still usable, the ease of input is overwhelming (personal opinion) ◆ I'm selling it because I want something smaller ◆ It's 40 years old, so please refrain from purchasing if you are concerned.