: Photographic flash units store high-voltage electricity even when turned off.
To further clarify the 124's capabilities, it's helpful to compare it with other models in FLASH's Monotron range, as detailed in the 100 series sell-sheet. This table is based on that official document: flash monotron 124 manual
Though programming may vary slightly by model, Flash Monotron timers share common features. The provides a good example: flash monotron 124 manual