This is a 40 degree egg crate grid for the Westcott 12" x 36" Strip Bank. Grids are essential accessories for any lighting system. A grid alters the shape and intensity of the light output from your softbox when it is mounted on a light head. Consider a grid as a painter would a brush, or a sculptor would a knife, or chisel. Use of an egg crate will result in a narrower spread of light. The spread of light will be determined by the density of the grid and the distance of the light from the subject.