Main function: a), Support Full ETTL Pass-through function when on camera Note: Speedlites on hot-shoe of transmitter support ETTL II / Manual / Multi Shutter Sync b), High-speed Synchronous The max. sync speed is 1/8000s, but some camera is just 1/4000s, and for those cameras and flashes who don"t suport HSS, the sync. speed is just 1/250s or less, different cameras have different Sync speed. c), Remote Control Function The parameter of flashes on hot shoe of receivers can be set up remotely through the camera manu directly. d), Supporting mixed mode. Note: Only FEC, FEB, Ratio and Shutter sync can be set in the camera side. Manua and Multi output need to be set on the flash speedlite. e), Awaking function When half-pressing the shutter button of the camera, the hot shoe flash on the receiver will be awakened. ( for those flash has wake up function ) f), Zoom Function Zoom Automatic: length will be charnged depanding on the changes of lens. Zoom Manual: Zoom length is within 24 - 105mm Zoom Lock g), Support Single-contact of camera and flash triggering ( the max. Sync. speed is 1/250s ) You can use it with Nikon camera or Nikon flash, but you just need to set up YN-622C in manual mode. h), Flash Fire Ratio with ETTL You can set up different flash fire ratio and FEC for those flashs on hot shoe of receiver. i), Support 2pcs AA batteries, ( 1.2v rechargeable battery ), Stand-by time is 60hours. j), Dimension: 89.5 * 53 * 39MM, net weight is 78g. Note: There is a PC Sync port for YN-622C transceiver, you can use RF-602 PC / PC Cable to connect it with flash. Package included: 2 x RF-622 C transceivers 1 x Instruction in English and Chinese (Original Manuefacture Package)