Opteka Wireless Radio Remote Release for Nikon D300, D200, D100, D2X, D2XS, D3 Digital SLR Cameras With the receiver connected to your camera's remote control socket Range up to 100m(320ft.) without obstacles Can activate auto focus, release shutter, activate continuous drive mode or keep the shutter open The shutter button can be pressed halfway or all the way. Number of control output channels: 16 channels available