Hoya 52mm PL Polarization filters are specially adapted glass that, when turned at an angle to a light source, will reduce glare from reflected surfaces. This polarizing filter is circular so it can fit easily on the end of almost any lens, containing a free spinning element for quick adjustment. FEATURES What this filter can do?This is PL polarizing filter/polarising filter is often placed in front of the camera lens in photography in order to darken skies, manage reflections, or suppress glare from the surface of lakes or the sea. ... The rotational orientation of the filter is adjusted for the preferred artistic effect. This is new open box filter, but top of the plastic storage case has some scratches.