It's much lighter than that.
The large panel is 1/2" inch white/black 20x30 foam core and the sides are 3/8" 10x30 and 20x30 inch white/black. There is a metal rod running up the 'spine' to attach to a light stand.
The lights are in place with 'contractor's' light fixtures, cheap fixtures that are glued to place with hot glue - the thing doesn't get hot enough to worry about too much heat.
The black is covered with a 3/8" foam core.
While not very elegant, the sides are taped with duct tape where permanently secured, and gaffer's tape when I use the sides for barn doors - bhoveyga couldn't see that in the photos. Foam core is tender, so I've glued some spots for the tape to cling to.
Controlling the light is 'old school'. If you need less, unscrew a bulb or move them out a bit. Light ratios are controlled with a meter. Mine is still an analog. Works like a champ, although I do have a digital meter on my shopping list.
This support for a tripod head was originally made for skiing and snowboarding videos done for our clients at a local ski resort as a 'snowboard cam', but with the eye-lets, you can bungee cord it to a car or practically anything for support.
We've taped drivers of cars trucks for commercials and wrapped the support around trees and fences, too.
Easy to make and it comes in handy for both film, video, and stills.