This Profoto Flat Front Diffuser for RFi 3.0 x 4.0' Softbox covers the front of your RFi softbox to conceal the recessed diffuser and give it a clean, flat appearance. It will also reduce output slightly, render smooth highlights in reflective objects, and hide hotspots. With the interior baffle and recessed front diffuser, the Flat Diffuser can be used in any combination. Utilizing all three will result in the softest appearance.