I tested this HP 33E with a basic test by pushing STO ENTER the screen showed a minus sign on the left, and then eight till the end of the screen. This means that the calculator is fully functional. When I push some of the buttons, there is a minus sign that shows up on the left. If I start with the number one and press up to number nine, there’s a minus on every press of the buttons. If I start with 3456789 there is no minus sign that shows up but as long as I push the one or the two first, then the other numbers will have a minus sign that shows up on the left-hand side.

It sounds like there is something loose inside. I read that overtime. Pieces of plastic or a screw could be loose inside the calculator.

You can see from the pictures the wear and tear on the box. It looks like it was owned by a library before as it is stamped with the number 3307 on the front of the box and there is a librarycard holder taped inside the box.

The manual is pristine. It is an excellent condition inside. This does not come with a battery.