definitive list of cases for each model calculator

[Kostas Kritsilas]

You can see the pictures of the cases, as you posted. The pictures that you posted do not show the texture of the vinyl. Nor does it show the variations in colour; some HP classic vinyl cases are brown, but not all. Some are very dark green. I cannot say that they arrived in those dark green colours, but the if the colour variation was due to sunlight, or chemical reaction, the sunlight/reaction must have been quite uniform, as the colour is quite even all over the case.

When I said from memory, I meant from personal memory, as in having seen both case types (HP-55 and HP-67, both belonging to friends) during my college days, and being surprised as to how different the cases were, even though the calculators were bought fairly close together in time.