The Canon ACK-E2 AC Power Adapter is designed to supply uninterrupted power for your camera while downloading pictures to your Computer, for extended work in a studio, or while viewing images while connected to your TV or VCR. It's compatible with the Canon EOS 5D, 10D, 20D, 20Da, 30D, 40D, 50D, 30D & D60 SLR Digital Cameras.