This is an incredible device. Two huge (approx 6" diameter) lenses slide on rails to allow you to focus your flash from 15-40 feet. No more worry about skewed backdrop lights! The rear plate has been outfitted for Norman LH heads. This means you can pop 4000ws pulses through this and with the big glass most of it is going to make it to its destination. Norman gear is pretty cheap right now (alas, I have tons of it) so you can pick up a head and pack for next to nothing. THE LS4000 HEAD IN THE PICTURE IS NOT INCLUDED. As configured, you can use the Norman LH2000, LH2400, or LH4000 (2000, 2400, and 4000ws respectively). You could easily adapt this to other flash heads. Inside is an aperture if you wish to adjust output intensity and a variety of custom apertures that have been machined to project a variety of patterns. This rig travels well in its custom fitted road case. The case is a super heavy duty model, professionally made. I'll kick myself for selling it but it has been sitting for years now. Looking for the pro that will put this to work.