Features: This set consists of a signal sender & two receiver trigger. Universal hot shoe interface, compatible with Canon, Nikon, Sigma, Olympus, Pentax, etc. (except Minolta SONY, for they use a special hot shoe). Globally univeral 433 Mhz 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 & stable. Energy-saving design with 12V 23A battery of transmitter & 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.