The TLRs are traditionally used with the "hammerhead" style of flash on a base mounted bracket and is plugged into the lenses pc socket. If your shoe mount flash has a pc cord it can be used too just as easily. The lens has a switch for different flash mode, but it should be set on X for the electronic. The switch is easily bumped to the wrong setting, so you may want to put a slip of tape or a drop of glue on the switch to keep it in place.