The Falcon Eyes PSL-15 Sensor + Hotshoe is essential if you wish to integrate your speedlite in with your studio flash unit(s) The front of the PSL-15 is equipped with a sensor, which measures the light from your studio flash units and triggers them. By using the TR-1 infrared transmitter, you can trigger your studio flash unit externally. Further, the PSL-15 is also equipped with an X contact.
The PSL-15 is equipped with a ¼” female screw thread enabling you to mount the hotshoe onto a universal light stand or tripod. The Falcon Eyes 4M4-UR Umbrella Holder can be combined with the PSL-15 to utilize the use of an umbrella to create a separate studio flash unit. Alternatively, the Falcon Eyes CLD-15 Tilting Bracket can be used in combination with the PSL-15 to enable you to position your speedlite in almost any direction. Both the 4M4F-UR and CLD-15 can be found in the optional accessories tab below.