Vello FreeWave Wireless Remote Shutter Release for Nikon DC-2 Connection - D90, D3100, D5000, D5100, D7000 16 Million Possible Channels / Operates on Radio Frequencies (RF) Direct Line of Sight Not Required / Operating Range up to 320' (100 m) Wireless Continuous or Single Exposures / Long Time Exposures Transmitter Can Fire Multiple Receivers Wireless Autofocusing & Triggering