The Hoya 52mm UX II PL-CIR Filter is a renewed version of the previous Slim CIR-PL model. It sits within the new 'UX' essential series, alongside the slim 'UX' UV filter. The 'UX' series is a design concept, aimed at users wishing to improve their photography. It offers HOYA's famous quality, at reasonable prices, with basic and contemporary features. 'UX' in the series name stands for "User eXperience", inspired by the memorable experiences that users acquire through using these filters. By naming this series 'UX', HOYA aims to offer users better individual experiences through all the activities connected with their photography. Features: Hoya 52mm UX II PL-CIR Filter Available in sizes from 37mm to 82mm diameter Controls reflections from non-metallic surfaces such as water, glass, leaves and blue skies Increases saturation and improves contrast Rotating frame controls polarising effect Slim filter frame - avoids vignetting on wide angle lenses, also holds a lens cap High quality HOYA glass The UX CIR-PL filter can be used with both digital and film cameras. It is used to control reflections from non-metallic surfaces such as water, glass, leaves and blue skies, increasing saturation and improving contrast. Polarising filters' structure incorporates a polarising film, sandwiched between two pieces of glass. The front part of the filter frame is able to rotate, allowing the polarising film to be positioned at the desired angle. Hoya UX filters use a low-profile aluminium frame which avoids vignetting when used with wide-angle lenses. They also have front threads which are able to hold other filters and lens caps. For more Hoya products see here.