The 52mm Drop-in Circular Polarizing Filter from Canon is used with long Canon lenses that accept rear-mounted drop-in filters. The filter is rotated from a ring on the outside of the filter mount. You do not have to remove the filter to use it. The glass is secured within a strong metal frame that slips in and out of the rear mount with ease. The degree of polarization can be seen through the viewfinder of your camera as you rotate the filter.
- Carry case.