... Working Distance: 30m New WANSEN PT-04GY Wireless Flash Trigger for canon nikon Pentax Olympus camera Specifications:4 channels with hot ... shoe connector for external flashesTransmitter Power: 23A 12V batteryReceiver ... 550EX, 540EZ, 520EZ, 430EZ,430EX, 430EX II, 420EX, 420EZ, 380EX;Nikon SpeedLite SB900, SB-800, SB-600, SB-28, SB ...