FlashWave-III Wireless Radio Slave Receiver Receiver for Remote Wireless Flash Trigger System - Receiver Unit Simple, Small, Reliable Hot shoe built into the receiver! No need for extra cables or adapters. Even greater operating range than FlashWave-2. Up to 600 feet (185 meters)! Max sync speed of 1/250s. 2.4 GHz operating frequency. 16 Channels! Built-in 1/4" tripod thread on the receiver unit for mounting on a tripod or light stand