This is the case for an incredibly bright bicycle headlight.  At roughly 2 inches square,
it's brighter than many car headlights.  Unlike the ones you see in Walmart, this has to
be made of metal.  The power going through it would quickly melt a plastic case.  Unlike
most of the parts in this gallery, this is a retail product, currently available for purchase.  
You can learn more about it, or purchase one at:

DesignShine Lighting