Some of the items I use in my kit include sheets of bristol board, black and translucent white plexiglass and diffuser panel made by cutting a ceiling panel in two. The ceiling panels I am referring to here are the ones you see in office buildings placed over long florescent tubes. They are VERY brittle so make sure you handle them with care.

In the picture above you can see the “other” use for the “T” connectors. I put short sections of PVC in them to support the translucent plexiglass as shown in the picture to the right. This gives you lots of room to slide an under-spot to “light” plexiglass for shadowless  photos.