To convert watts into amps, you need to know the voltage of the circuit or device you are working with. The formula to convert watts to amps is: Amps (A) = Watts (W) ÷ Voltage (V) Example: 5W LED = 5÷12=0.41A Work out run time: 10Ah ÷ 0.41 = 24 Hrs If the battery was to power 3x the lights 10 ÷ (0.41+0.41+0.41) = 8hrs Please Note: The cut off voltage of the Equipment may impact the run time depending on the chemistry discharge curve characteristics.