I am planning on buying my first curta, and I would like a type 1.

I have heard that they had metal clearing rings and winding levers on the early ones, but when exactly (what serial no.) did they switch? I see some with the domed top winding lever, does that mean it is metal? how do you tell which ones have metal clearing rings?

Hi zev


There is no sharp border between the different types of clearing rings or winding levers...



I would suggest an earlier full metal version!