AW Mattebox Matte Box for 15mm Rail Rods System Film Movie Camera Photography Adjustable Angle Designed for most DV cameras with wide angle lenses. Used on the end of a lens to block the sun or other light source to prevent glare, which functions as that of lens hood. Besides, matte box is also be used to hold glass or plastic filters in place in front of the lens. This Matte Box could be adjusted the height (up to 45mm) according to the lens of camera on the rail rod system Top and flank barn door are easily adjustable the angle to meet you; and removable, convenient to carry It works with standard 15mm rail rod support systems, and fits lens from 43mm to 77mm sizes.