B+W 40.5mm Clear UV Haze with Multi-Resistant Coating (010M) Product FeaturesSize: 40.5mm Brass Ring for higher Quality Image Highest possible polishiing technique World's best optical glass New thinner Pro mount. No vignetting USA Warranty Product DescriptionSize: 40.5mmFrom the Manufacturer Protect Your Lens while Reducing UV Exposure This UV Filter blocks the invisible Ultra Violet component of light from the sky, which can cause blur and to which many color films react with a blue cast. These filters should be called UV-Blocking Filters, because there are filters for technical applications that pass UV radiation and block all the other wavelengths. ...