The USB Dummy Battery Cable allows you to use an optional 5V USB power source to power a camera . The dummy battery features a 40" cable with a USB Type-A connector. Battery status is passed to the camera using a built-in emulator chip.
The USB power source should provide at least a 2A output. Note that USB ports on computers deliver only 1A, and many common USB power banks and power adapters are also limited to 1A, so a using separate power adapter is recommended
It's available for canon series camera that uses the following batteries such as :e6, e8, e10, e12, e17,
Its available for nikon camera series that uses the following batteries such as el14, el15
It's available for sony camera series that uses the following batteries such as fw50, fz100 , f970