The Manual Flash Trigger for Canon & Nikon Housings mounts on your Sea & Sea housing, connects to your camera's hot shoe, and translates the camera's flash signal into LED light that triggers your strobes via fiber-optic cables. The flash trigger is powered by a CR1632 lithium battery (not included), so it doesn't draw from the camera's own battery, and it has a battery status indicator. The trigger will last for approximately 12,000 activations and has a continuous standby time of 100 hours. Only manual flash is supported.