Prevent burning out your camera | Flashpoint - Official Website

If the camera sync voltage issue is not taken into consideration, the sync voltage of some old-fashioned flash units could likely damage the camera. However, this problem does not exist when using wireless devices or PocketWizards. By browsing relevant information, you can find out whether the combination of the flash unit and camera being used is safe. The article also states that several older flash units recommended previously are all within the safe usage range.