Camkitmate SYK-4 Wireless Hot Shoe Flash Remote Controller Slave Trigger With PC sync Port 1.This Hot Shoe Flash Remote Slave Trigger has a sensor to sense light from the master flash so as to trigger the slave flash wireless. 2.The hot shoe adpater also comes with a PC sync port output 3.The SYK-4 flash remote controller is harnessing optical theory making the master flasher to control remotely the auxiliary one to flash synchronously without the need of connecting wires. It features small in volume, good-looking in exterior, high inflexibility and stable in performance, it can also artificially create different kinds of effect and take special photos. Suitable For: All Hot-shoe Flashgun Note: 1. this adapter doesn't fit CANON TTL flash (example 580EX/EXII 430EX/EXII) 2. this adapter doesn't fit Sony and Minolta flash Package Included: SYK-4 Flash Remote Controller x 1