The Nikon EP-5A Power Supply Connector for D3100 or D5100 lets you power your D3100/5100 camera from the EH-5A or EH-5 power supply and that way save battery power. This connector will come in handy when the camera is being used indoors for extended periods use such as for studio sessions, when uploading files to a PC, or when playing back media on a TV.
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