Curta Models Curta ModelsThe Curta was produced in two basic models:
There are two major variations of the Type I: early and late. The early models have a metal crank and metal clearing lever, and came with a metal carrying case. In the mid 1960s Contina supplied the Type I with a plastic crank and plastic clearing lever, and shipped the units with a plastic carrying case.There are three major variations of the Type II : black body, grey body, and grey body with plastic crank and plastic clearing lever. The black body Type II looks more like the Type I because the main body is all black. All black body Type II's came with a metal crank and metal clearing lever. In the late 1950s, Contina started producing the Type II with a grey crackle painted body and collar. These Curtas continued to have metal cranks and metal clearing levers until the mid 1960. Then, as with the Type I model, the grey Type IIs were supplied with plastic cranks and plastic clearing levers.
The factory phased in appearance changes over time. As a result, there are many "halfway" model variations. It is these units that often spark extreme interest in collectors...
Functional Differences
| Model | Type I | Type II |
| "Entry/Counter/Results" Readouts | 8 x 6 x 11 | 11 x 8 x 15 |
| Data Entry Register (Multiplicand) | 8 digits | 11 digits |
| Crank Turns Counter (Multiplier) | 6 digits | 8 digits |
| Result Register (Product) | 11 digits | 15 digits |
| Add or Multiply to | 11 places | 15 places |
| Divide To | 6 places | 8 places |
| Diameter | 2 1/16 in. (53 mm) | 2 9/16 in. (65 mm) |
| Height | 3 3/8 in. (85 mm) | 3 5/8 in (90 mm) |
| Weight | 8 oz. (230 g) | 12 1/2 oz. (360 g) |