Product Description The Strobies Pro-Flash Receiver is used in conjunction with the Pro-Flash Transmitter to trigger the Strobies Pro-Flash. The 165 (50m) working range gives you the freedom to move around and shoot with long lenses, should the situation call for it. The Pro-Flash Receiver connects to the Pro-Flash via USB and does not need its own power supply. Product Specifications Channels = 16 Range = 165 (50m) Max Sync Speed = 1/250sec Power Source = USB Housing = High Impact Plastic Mounting = USB Frequency = 433MHz The Strobies Pro-Flash Receiver includes: 1 - Strobies Pro-Flash Receiver