The Elinchrom EL 26117 Rotagrid for Rotalux 70x70 cm is an "egg-crate" diffusor designed to be placed in the front of the Rotalux 70x70 cm (27x27") soft box, softening the light, and controlling the beam by directing the diffused light in a relatively narrow pattern forward from the softbox, while preventing light spill to the sides. For soft, but directional, light.