http://www.nikonchat.com/oem-nikon-camera-batteries/
Is it okay to use an OEM battery for my camera (Nikon D40)?
They are much cheaper, but want to make sure to use one I do not mess the camera in any way.
I would not consider. If you are willing to buy a camera for about $ 450 you should not having to worry about buying an extra battery (you get a better deal if it costs me $ 100!). Nikon strictly warns against all products not -Nikon, but the batteries are the most serious. Non-OEM batteries could have serious shortcomings for life and may damage the camera in severe cases. Just go with the nikon battery.
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