These are four different parabola templates for tactile drawing.
In my own experience, blind pupils find it easier to use the negative versions, as these are easier to align in the coordinate system. The edges can be aligned relatively well parallel to the x- and y-axis.

Drawing templates are available for dot grids of 1 and 2 cm. There are also different sizes. For example, this drawing foil can be used:

https://www.inklusion-jetzt.de/Unterrichtsmaterialien/Unterrichtsmaterialien/Zeichenfolie/Punktgitternetz-27-x-34-cm-x-und-y-Achse-mit-1-0-cm-Rastereinteilung.html