Overview:4 Channels Selectable Wireless Flash Trigger Receiver V2s, Works with V2/V2s wireless flash trigger only Designed for Vivitar 285HV, Sunpak 433, Sunpak 383, Olympus FL-36 & other flashes which (1) comes with a trigger voltage lower than 12V & (2) could not be triggered by V1 or V2 receivers Transmitter Power: 23A 12V battery Receiver Power: AAA Battery Maximum Working Distance: 30m (open area, without interference) Working Frequency: 433 M Hz Comes with PC sync port Specification: Weight Approx: 140.5g Size Approx:6 x 4 x 14