Hangingpixels and I recently purchased a Boling BL-400WPD Flash unit (We nicknamed it ChinaBee because of the close resemblance to AlienBee) We decide to install an external power socket so the unit can be powered by wall socket or external high capacity battery for extra flashes. WARNING! Before you attempt this, you must have good knowledge of electronic and soldering technique! "NELLYPRO DOES NOT ENDORSE THIS PRODUCT NOR RESPONSIBLE FOR ANY SPOTANOUS COMBUSTION OR EXPLOSION after this modification. Parts list: (all parts are purchased from Jaycar Australia) Battery: 18amp Seal Lead Battery CAT# SB2490 2.5mm Right angle DC socket CAT# PP0515 2.5mm Bulkhead Male DC power connector CAT# PS0524 Red/black hook up wire What it does. A 2.5mm bulkhead male DC power connector is installed to the chassis, this connector taps straight into the 12V circuit of the unit in parallel. When the 2.5mm DC socket is inserted into the power connector, it cuts the circuit of the internal battery supplying the power to the unit and feeds the power from the external power supply. In this photo, it is showing the unit being operated without the internal battery installed.

The Caon A-1 with Power Winder A and External Battery Pack A attached.