The item mentioned above is an original battery for your Nitro 5 AN517-51-55MM. It is an excellent replacement battery for your existing or defective Nitro 5 AN517-51-55MM. It can also serve as an additional spare battery for on-the-go use. Handling and charging are as usual, hassle-free with the standard power supply or charger. A high level of safety is provided by the protective electronics against overcharging and short circuits. All batteries are new and unused. Our own quality assurance ensures a high standard of quality. Note: Unless we explicitly state that this is an original product, we supply a compatible product. This means it is by no means an original product from the manufacturer and is therefore not produced or recommended by them. All brand and product names are the property of their respective owners and are only used for compatibility description.