Keep solar panel clean. If solar product does not light up after it has been used for around 8-12 months, replace the rechargeable batteries as they may be weak or worn out. Recommended battery 1pc AAA 1.2V 300mAh, Ni-MH or equivalent must be used for best result. Open the battery compartment cover and replace 1pc AAA (rechargeable only). Be sure to observe the correct polarity.