Features:Equipped with overvoltage and overcurrent protection, when the output current and voltage are too high, the charger will stop working to prevent safety accidents caused by it.Equipped with anti reverse connection function, in case of reverse connection of positive and negative poles, the charger automatically protects and stops charging, avoiding dangerous accidents and preventing overcharging of the battery.Mesh heat dissipation holes provide good heat dissipation and high temperature resistance.Excellent expandable battery compartment, capable of charging multiple battery models simultaneously, with stronger compatibility.Package includes: 4 x Dual Slot Wall Charger.Specifications:Input voltage: 100-240V 50/60HzOutput voltage: 4.2VOutput current: 500MACharging time: 4-8 hoursScope of application: Suitable for 18650 lithium electronic rechargeable batteriesInstructions:No battery, green indicator light onWhen charging, the indicator light is redWhen fully charged, the indicator light turns green. It is recommended to continue charging for 1 hour after the green light, which is the trickle state and the battery level is more sufficientGenerally, it takes about 4 hours to charge a single 18650 (1000mAh) battery, and if two batteries are charged simultaneously, the time required is doubledPackage includes:4 x Dual Slot Wall Charger