Yongnuo RF-603 II allow wireless radio control of the camera and triggering of system and studio lights from up to 270m away. It has a radio remote control function for triggering the camera. It operates at a frequency of 2.4 GHz and has the ability to set as many as 16 channels, which guarantees reliable operation of the device in all conditions.In the new version of the trigger, the switch has been relocated, making use even more convenient. In addition, the switch has become two-stage - it is possible to turn on the RF-603 II as a transmitter, or as a transmitter/receiver. This provides more convenient use of the trigger (it is possible to trigger connected lamps "handheld" without any problems) and allows to extend the life of the batteries used. Unique for this kit is that it contains two modules, each of which can work both as a transmitter and receiver. This makes the kit very versatile and easy to expand.The RF-603 II can simultaneously trigger the lamp remotely and the other on the camera. The RF-603 II series lamp triggers operate at 2.4 GHz. This guarantees trouble-free operation and no interference. The device is powered by popular AAA-type batteries.This small kit is an absolutely essential device in your photography bag! Take the flash off your camera! With the Yongnuo RF-603 II Wireless Trigger, you can shoot with a sync time of up to 1/250s.You can also use the Yongnuo RF-603 II as a wired or wireless remote control for your camera with an effective range of 100m (up to 270m in tests)!The device supports a receiver flash excitation function. We also offer additional receivers for this system! SPECIFICATIONS: FEATURES: Radio remote control for camera or trigger hose Wireless triggering of lamp system and cameras - any number Wireless triggering of reporter lamps Wireless triggering of studio lamps Frequency: 2.4 GHz Number of channels: 16 Range: up to 100m (up to 270m in tests) Power supply: 2 AAA batteries Maximum sync time: 1 / 250 sec Camera sync socket: 2.5mm Lamp sync socket: standard PC, hot shoe Top ports: hot shoe Shutter: two-stage: 1-autofocus, 2-trigger Supported flash port voltage: 5V (transmitter), 300V (receiver) Dimensions: 80 (L) x 30 (W) x 20 (H) mm Antenna : built-in Weight : 66g