The square shape hoods designed for use on medium format 120 SLR film cameras of all brands. They are suitable for the three medium formats 6* 4.5cm, 6* 6cmand 6* 7cm. Medium format 120 SLR lens hood. The main function of the lens hood is to shade the lens from stray light, improving your contrast and image quality. It will also protects the front barrel from the inevitable impacts against walls, door frames, and other real-life obstacles and in inclement weather, it can assist in keeping moisture or wind-blown debris off the lens.