The 2.4GHz wireless frequency is suitable in most countries and guarantees high speed, distance and stability. Within capacious areas, the remote control distance may reach to 100m. | The synchronization speed can reach to 1/320, depending on the situation. | The new RF-603 II is improved version of RF-603, it is a remote shutter release as well as a multi-functional flash trigger which can synchronously trigger flashes and studio strobes. | Only 2 AAA batteries are required as power source for each item. | Through the transceiver based system each item can be used flexibly as trigger or receiver.