The number of comparable Campani screw-barrel microscopes known exceeds ten. All have similar optics and are of similar construction and size; one has a cylindrical case. The fleur-de-lis stamped on this case most likely represent the emblem of Florence.

The lenses are well made of clear glass, but with many very small air bubbles, which is normal for the period. The image is good, with a magnification of about x30.