2sets of Yongnuo Rf-603 C3 Wireless Remote Flash Triggerr/wireless Shutter Release Transceiver for Canon for Canon 1d 1ds Eos5d 5d2 50d 40d 30d 20d 10d Works as a wireless shutter release control: &lt;br&gt;Auto focus, continuous shooting, long exposure, half-way pressing, full-way pressing is supported &lt;br&gt;Depending on the camera model a special shutter release cable is included in the package Package includes: 2xTransceivers 2xReceiver 2x2.5mm port Shutter release cable cable Channel:15 different channels and all channels Release:Half-way press, full-way press