Unwanted light can ruin your shot. Protect your lens from light with the Dot Line Matte Box. It's adjustable height can help fit the lens of your choosing. This matte box is great for lenses with 86mm or smaller filter threads. The top, bottom, and side flags are all removable for more customization you might need for your shot. However it doesn't only come with the four flags, but it also includes the two cowls for different lens sizes that will help prevent any light from entering in between the matte box and your lens. A must have piece of equipment for unwanted light! 

B&H Link: http://www.bhphotovideo.com/c/product/1035457-REG/dot_line_dl_v_mb3_matte_box_with_filter.html