I currently only have a single studio flash, as I used to use my ex-flatmate's strobe as its pair. Now I moved, and am left with just one strobe and one potato masher-sorta flash. The single strobe also didn't want to sync by the built-in flash of the 40D frame, so I HAD to get the potato masher working. Originally the damn thing uses 6 AA-cells, which meant I would've had to buy 6 rechargeable batteries and two chargers for rechargeable batteries to work.... It's just too much to feed a single free flash So instead I cut some pieces of acryl and PCB and bolted it together with M4-screws Also added some capacitors to the pancake to even out the load peaks. Then just plug in the wall adapter and bob's your uncle. In case someone missed it, the new acryl-piece perfectly replaces the old battery holder without any modifications to the (antique?) flash itself.. This saves batteries, and the WORLD ...and I can finally start taking new hardware shots.