Note: **It is normal to select the mode on the charger without connecting it to the battery or batteries that need to be charged and only OFF is displayed, you must clip the positive and negative terminals to the battery or batteries before selecting the mode to be effective. **Also this product is only a charger and cannot work without being connected to AC power. How to use: Before charging: Check your battery parameters is compatible to the charger. When charging: 1.Connect the red clamp to the positive pole (+), black clamp to the negative pole (-). 2.Connect the charger with AC power source, the charger will start to operate. 3.Once the battery is fully charged, the battery bar on screen will in “FUL” status. Charging completed: Keep the charged status in 1-2 hours is highly rec.