[. . . ] To ensure proper operation, read this manual thoroughly before using the product. After reading, be sure to keep it where it can be seen by all those who use the product. [. . . ] After reading, be sure to keep it where it can be seen by all those who use the product. wARNING · The EN-EL2 is a rechargeable battery pack for use only with Nikon digital cameras. â· When recharging the EN-EL2, use only the MH-60 Battery Charger. Do not short the positive and negative battery terminals with a metal object such as a necklace or keys. Failure to follow these instructions could cause the battery to leak corrosive liquids, overheat, or explode. â· When recharging, the ambient temperature should be between 5Â35ºC (41Â95ºF). You may notice that the battery is hot directly after use or recharging; this does not indicate a malfunction. â· Even when fully charged, the battery will discharge more rapidly in cold conditions. It is recommended that you keep a fully-charged, spare battery on hand. â· A marked drop in the time a fully-charged battery retains its charge indicates that the battery needs to be replaced. [. . . ] It is recommended that you keep a fully-charged, spare battery on hand. â· A marked drop in the time a fully-charged battery retains its charge indicates that the battery needs to be replaced. [. . . ]