Specification: YN-560 IV Flash Speedlite is a combination of YN-560 III and YN560-TX,, it has built-in wireless trigger system, so you can not only use it as flash speedlite, but also a flash controller Transmitter. Features: a, TX Master Flash mode: When you set up YN-560IV as TX mode, it can be used as a flash controller transmitter, it can trigger YN-560 IV ( RX mode )and YN-560 III ( RX mode ), and also can be used with RF-602, RF-603 II, RF-605 together. b, RX Slave Mode: When you set up YN-560IV as RX mode, you can use it with YN560-TX flash controller, and RF-602, RF-603 II, RF-605 single transceiver. c, Manual mode d, Multi mode e, S1 / S2 mode — You should use those two modes off camera f, Power saving mode g, Overheating Protection h, Manually set and zooming position g, PC Synchronous Port Suit for: All cameras with ISO standard hot shoe. Yongnuo RF-605, RF-603 II, RF-602, YN-622C, YN-622N, YN560-TX Yongnuo YN-560 III Yongnuo Flash Battery Pack SF-17 C / SF-18 C Package Including: 1 x YN-560 IV Flash Speedlite 1 x Protecting bag 1 x Original box 1 x Manual in Chinese and English.