[. . . ] Thank you for your purchase of an MH-22 Quick Charger for up to two Nikon EN-EL4 or EN-EL4a rechargeable Li-ion batteries. The MH-22 is equipped with battery calibration feature and charge lamps that glow, blink, or turn off according to the battery charge state. [. . . ] After reading, be sure to keep it where it will be read by all those who use the product. Precautions for Use: MH-22 Quick Charger IMPORTANT The Nikon MH-22 can be used to recharge Nikon EN-EL4/EN-EL4a rechargeable Li-ion batteries only. ⷠUnplug the power cable from the power outlet when not in use. ⷠYoung children should be supervised to ensure that they do not play with the appliance. Precautions for Use: Nikon EN-EL4/EN-EL4a Rechargeable Li-ion Batteries IMPORTANT The internal temperature of the battery may rise while the battery is in use, especially when the ambient temperature is high. If you attempt to recharge the battery while the internal temperature is elevated, the battery will not charge or will charge only partially. When recharging the battery, the ambient temperature should be between 0 to 40 °C (32 to 104 °F) or the battery may not fully charge or may not function properly. Should you notice smoke or an unusual smell coming from the charger, unplug it, taking care to avoid burns. Insert the battery (terminals first), aligning the end of the battery with the guide and then sliding the battery in the direction indicated until it clicks into place (Figure 2-b). The Charge and Calibration Lamps There is one set of charge lamps, while each chamber has its own chamber and calibration lamps and calibration button. [. . . ] If the chamber and calibration lamps flash on and off in sequence when a battery is inserted, a problem has occurred with the battery or charger during charging. Improvements to this product may result in unannounced changes to specifications and external appearance. [. . . ]