Features: Universal hot shoe interface, compatible with most DSLR camera. Globally univeral 433Mhz frequency, 4 channels. With studio flash interface, can trigger several kinds of studio flashes. Transmitting distance up to 30M, no limits with directions or angles. 1/4" nut can be connected with tripod or light holder to make flashlight safe and stable. Speedy frequency regulation, convinient for photographers to shoot. Energy-saving design with 12V 23A battery of transmitter and 2 AAA batteries(not included) of receiver. Comes with a PC sync cord for cameras without hot shoe socket. Note: This trigger do not support TTL function. How to use: 1. Insert the transmitter's hot shoe socket into your camera's hot shoe jack, plug the flash onto the receiver, switch ON the receiver. Make sure the channel selector of both transmitter and receiver at same channel. Press the Test button on the transmitter to test before shooting. 2. If your camera has not hot shoe socket for connecting the transmitter you can connect the transmitter to the camera by the PC Sync Cord provided. (only the old camera needed). 3. You can trigger both the flashgun and studio lights with this flash trigger. If you use the receiver on big studio strobe flashlight or AC slave flash, you can just connect the receiver to the studio strobe flashlight with 3.5mm or 6.35mm jack plug PC Sync cord(not included). Specifications: Power of transmitter: 23A 12V mini battery(included) Power of the receiver(AC): 2 * 1.5V AAA Alkaline Battery(not included) Outdoor working distance: max. 30m / 90feet (open area, no fraise) Indoor operating distance: max. 25m / 75feet Channel: 4 channels Frequency: 433Mhz Synchronous speed: Max. 1/250sec Color: black Material: metal + plastic Package size: approx. 7.5 * 6.5 * 4.6cm / 2.25 * 1.95 * 1.38in Package weight: 86g / 2.99oz Package includes: 1 * 4-channel Transmitter(23A 12V battery included) 1 * 4-channel Receiver(AAA batteries NOT included) 1 * PC Sync Cord(2.5mm to PC) 1 * User Manual