· USB Charger Safety Protection Under voltage protection, over voltage protection, over current protection, over temperature protection, short circuit protection, excellent heat dissipation design .the product excludes the sale of restricted Standalone lithium batteries.· Compatible Devices: Battery for flashlights, headlights, fans, digital cameras, radios, speakers, surveillance equipment.· Charging display-This Battery charger with Red/Green led light display, And the charger will display the status of each rechargeable battery when charging,Automatically detects battery power status and automatically stops charging when complete.· 4 bay Battery Charger :4 charging channels can charge the battery independently. 4 slots can be adjusted according to different battery sizes.