The Kase Sony Alpha Clip-In Filter ND16 (4 Stop) is your perfect choice when you want to reduce the amount of light captured in your photos. You can use it to increase the exposure times for your pictures, allowing for light trails and smooth water. Long exposure photography helps to capture movement in unique ways or reduce crowded roads to empty ones as well. The Kase Sony Alpha Clip-In Filter offers four stops of exposure reduction, allowing you to control shutter speeds and aperture to create the desired level of motion blur or depth of field. It is constructed of B270 optical glass to offer a perfect combination of strength and durability. It features a multi-coating that reduces haze and acts as a protective cover to the image sensor when shooting in tough situations. Best of all, it is easy to install and simple to remove.