Cowboystudio NPT-04, 4 Channel Wireless Hot Shoe Flash Trigger Receiver for Sony Alpha Digital lSLR Camera and Sony Flash
Includes: 1 x Transmitter (with 23A 12V battery installed)1 x Receiver (Powered by 2 x AAA, Battery is not included)1 x Sync Wire Cable (no need to use it for most flashes)4 channels with hot shoe connector for external flashesTransmitter Power: 23A 12V batteryReceiver Power: 2 AAA Battery (Not included)Maximum Working Distance: 30m (open area, without interference)Operates on Frequency: 433MHzHighest responding time up to 1/320sTriggering life: up to 20,000 times