The Strobies Pro-Flash Transmitter Receiver for TLi-CTLi-N is used to trigger the Strobies Pro-Flash TLi-CTLi-N. With 16 channels you are able to individually program & group up to 16 Pro-Flash units. Like the Pro-Flash the Transmitter & Receiver feature simplified controls letting you adjust the flash power from the camera position. The 50m 162 working range gives you the freedom to move around & shoot with long lenses should the situation call for it. The Transmitter runs off of two AA batteries while the Receiver plugs directly into the Pro-Flash via the Wireless Control Port located on the side of the unit & does not need its own power supply. The Transmitter for TLi-CTLi-N can also be used to control the power of other Pro-Flash lights including the Pro-Flash One Eighty & Pro-Flash 360 additional receivers required