We highly recommend this Charger for Head Lamp and Flashlight Battery Black (US Standard) to you. It features slim and compact size， allowing you to carry it conveneintly. This charger offers overload circuit protection and reverse protection， durable to use for a long time. When the light is green， it is in normal standby condition， the red light is in charging condition. And when the battery voltage is up to 4.16V， the red light will turn to green， under this situation， it is still in charging condition with low current.                                    Features             Automatically detects the type of battery<br> Auto-off when charging is finished <br> The indicator is red during charging， and turns green when charging is finished<br> Reverse protection， and the charger refuses to work when you put the battery in a reverse direction<br> Perfect fitting and satisfaction guaranteed<br> Suitable for flashlight and headlight battery   <br>                                                            Specifications             Material     PC    <br> Dimensions     (2.36 x 2.20 x 0.98)" / (6 x 5.6 x 2.5)cm (L x W x H)    <br> Color     Black    <br> Weight     1.31oz / 37g    <br> Standard     US Standard    <br> Max Voltage     4.21V     <br>                                                             Package Includes            1 x Charger<br>