It eliminates hot spots and is made with high-quality fabrics. All Profoto Softboxes have a recessed front that allows you to attach a mask. It is compatible with the Profoto Softbox line and cannot be used with the RFi, OCF, and Clic Softbox ranges. In addition, place the Softbox with the Edge Mask behind your subject and watch as the frame of light illuminates the edges while keeping the background black. Simply attach the Profoto 2 x 3-Feet Edge Mask Rectangular to your Softbox using the Velcro attachment and let the completely dark area in the center create a beautiful contour light around your subject as well as an intriguing catch light.