This is a 7" diameter clip-on 40° honeycomb grid, which will fit the Norman Monolight reflectors, or any other strobe reflector that accepts a 7" diameter, .5" thick grid.
Grids are essential accessories for any lighting system. A grid alters the shape and intensity of the light output 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.