The 67mm UV-Haze #010 MRC MASTER Filter from B+W blocks UV light, which can cause blurring and a blueish cast. An invisible component of daylight, UV light is more intense in pure sea air and high mountain regions. This filter is color-neutral and can be kept on your lens even when you don't need it, simply to protect the front of the lens. The filter element is made of glass and is highly transparent.