The polarization shade lenses are only mounted on our HORIZON ULTRA. There is one polarization shade glas each in horizon and index direction.
This extra simplifies the handling of the sextant during observations.
By turning the glass, the brightness of the celestial object can be adjusted continuously. This has the advantage that no shade glasses have to be removed or added during the observation and thus the celestial object can be held more easily in the field of view.
Retrofitting the polarization shadow glasses to other sextant models is not possible.
