PT-16 16 Channels Wireless Remote Speedlite Flash Trigger+2 Receivers for Canon Nikon Metz Minolta Sigma 1. 16 Channels Transmitter x1(12V 23A battery inside) 2. PT-16 Receiver x2(AAA batteries do not provide) 3. PC Sync cord for camera (2.5mm to PC) x1 For most of CANON NIKON OLYMPUS YONGNUO speedlight PT-16 16 Channels Wireless Flash Trigger+2 Receivers for canon nikon Metz Minolta Sigma