The Medium Quartz Plus is designed for use with large open-face hot lights. It is rated up to 6,000 Watts and diameters from 9 to 21.5 inches. It may also be used with a strobe light, but this is not economical in the long run, since adapter rods would be required for the attachment of a strobe ring; this box has shorter rods.The depth of the Quartz Plus is ideal for an open-face light. It is shallower than the Daylight Plus Bank designed for Fresnel Lights.Use this box for the softest light possible. The "Plus" designation means the face of the box is removable. Chimera makes different strengths of diffusion material for front face applications. This softbox comes with a one stop diffusion cloth, and additional 1/2 and 1/4 grid cloths. Substituting a half or quarter difusion, or taking out the interior baffle will result in more contrast, slightly more light transmission, and less softening of the light.