Safely regulates and reduces the flash sync voltage of the flash or strobe unit. This is especially important when pairing current automated SLRs or digital cameras with older flashes or lighting systems. The SMDV Hotshoe Safe Sync Adapter mounts directly to a camera"s hot shoe and provides a hot shoe on top and a PC female flash connection on the side. You can have a flash connected to the hot shoe and, at the same time, a flash being triggered by the PC female connection.