Features: LCD digital display voltage, current, temperature, battery capacity in real time, convenient to read. Intelligent adjustment of current and voltage, automatically stop input current after full charged. 3 stages charging: constant current charging, constant voltage charging, floating charging. Pure copper transformer, stable output, high conversion rate, energy saving, large capacity, etc. Overcharge protection, short circuit protection, reverse connection protection. The shell is made of ABS flame retardant material, insulation, flame retardant, high temperature. Universal for most type of car and motorcycle batteries, lead acid, agm, gel, vrla. battery) Specifications: Material: ABS + Copper Model 12V2A(20AH) Product model D.C-12V Input voltage AC-110-220V Output power AC-28W Output voltage D.C=13 8V-15 5V Output current: D.C=2-3A Note: Not use for Lithium Battery. Red clip is connected to battery positive. Black clip is connected to the battery negative. If the LED color can't be changed from RED into the GREEN , it means that the battery may be broken and you need to check if the battery is broken in advance. for the battery if you don't use it for long time or Lack of electrolyte,the voltage will be much lower and the battery will be easy got broken and battery will not been charged any more. Package Included: 1*Battery Charger