Model Number:RB40 -AAAMaterial: Lithium-ion batteryCharging Method: Type-C usb cableCharging Voltage: 5VNorminal Voltage: 1.5VTypical: 400mAhCapacity: 750mWhDiameter: Min 9.8mm, Max 10.5mmHeight: Min 43.5mm, Max 44.5mmWeight: 6.9(+-0.5)gCharging time: 2 hours (+-0.5)LED Indicators: Blink when charging,Stay on when full chargedShort-circuited/over-flowed/over-charged/over-discharged protection: YES