The B+W 77mm UV Slim SC 010 Filter is a general use, clear filter that helps to absorb ultraviolet light and reduce the bluish cast of daylight. No additional coloration or contrast is provided, allowing you to pair this filter with others. The UV filter is also useful as a general protective filter to leave on lenses at all times. Filters help to reduce dust and moisture from reaching your lens element and provide additional protection in case of drops or situations where scratching could occur. B+W filters are constructed from high quality Schott glass for increased optical clarity and color fidelity. They feature a brass filter ring for durability as well as jamming prevention. The slim filters are specifically designed for use with wide angle lenses and are only 0.1 / 3mm thick. They do not have front threads for stacking additional filters. Note: This filter ring's outside diameter is slightly larger than the actual thread size, and because of this you may be unable to attach the lens manufacturer's bayonet-mounted lens hood to the lens while using this filter. This is dependent on your specific lens and how thick the front rim of the lens is; with thinner, low-profile lenses usually being affected more.