The 5 x 5' Skylite Rapid Midi Kit from Lastolite is built around a lightweight but sturdy 5 x 5' aluminum alloy frame that accepts the kit's reversible white/silver reflector fabric, as well as the included 1.25 stop diffuser.
Quick change fabrics clip onto the frame with a small gap between the frame and border that serves as a vent for stability in windy locations. The white fabric gives you a soft neutral bounce light, while the more specular silver side yields crisp contrast and high reflectivity that comes in handy for long throw or fashion purposes. The translucent fabric can be used as an overhead scrim to tame harsh sunlight or as a diffuser for a large light source, like a Fresnel. Optional fabrics are available, as are grip heads, floor brackets, and crossbar handles.