Wireless Remote Shutter Release Trigger Receiver for Sony A900 A850 A700 A550 S1R By Fancierstudio Effective remote distance (open space) of 30 meters 16 unique channels support multiple users Strong interference-resistance capacity Suit For:Sony A100 / A200 / A300 / A350 / A450 / A500 / A550 / A700 / A850 / A900 # Minolta Dynax 7D / 5D # Minolta Dynax 9/ 7/ 5/ 4/ 3 # Minolta Dynax 807si/ 800si/ 700si/ 600si/ 505si Wireless bulb shutter and continuous shooting function