Features: Built in high precision voltage detection circuit (over charge 3.7v-4.3v, over 2.3v-3.0v) The current can reach 5A Protect plate with nickel, suitable for spot welding The size of the protective plate 53.4*17.4MM The range of working temperature - 40 degrees C ~ +50 C Low consumption current. Three section 18650 lithium ion rechargeable battery.