Pro-Sync Wedding System with in-line PC hook-up for bracket mounted flash. Provides SURROUND-SYNC omnidirectional performance and shoots around corners. Comes with "BATTERYLESS" receivers.Includes the Following Features:Battery-Saver transmitter circuits.Full cordless operation.Direct receiver plug-in for all flash units with standard "H"-prong ("household") receptacles, and standard "PC" terminals as well.Direct locking shoe-type transmitter mount for all cameras with hot shoes (PC cord included for others)."Open-Flash" test-fire button on transmitters.No awkward antennas.Not affected by sunlight or indoor light.Absolutely film-safe.360- degree sensitivity.ISO sync voltage standards eliminate shutter contact wear.Infrared pulse tube good for half-million shots (replaceable).People-safe, no health risks.Legal world-wide (unlike radio slaves).Ultra miniature, rugged circuitry.Immune to all interference (radios, TV's, microwaves).Immune to proximity of metal or cement walls.Will not cause interference to radios or TV's.Non-jammable. Super strong Lexan receiver housings