Battery Power Pack for our battery voltage connectable lights range. When you have chosen the lights you require from our battery voltage lights range, then it is essential that a power pack is purchased to power them. This power pack (FL-152) will power up to a maximum of 250LEDs or 60 festoon LEDs (3 sets). The power pack requires 3 x D cell batteries, has a 50cm lead cable (from the box to the first light) & a 2 function dial which enables you to choose a steady on or twinkle display. The dial also means that you can choose between on/off for occasional use or timer for clockwork displays. Once the function dial is set to timer, the internal computer starts a 24hrs cycle which will power the LEDs for 6hrs then turn of for 18hrs. For example: once activated at 4pm, the timer will light your display until 10pm then automatically turn off until the same time the next day, repeating every day. The power pack can provide amazing life thanks to its 3 x D cell batteries which can light for at least 180hrs, that's a whole month for 6 hrs each day. Connecting less than the maximum number of LEDs or setting the function to twinkle will pre-long the battery life even more. The battery power pack is IP44 rated for outdoor use & is designed for easy battery replacement by removing only 4 screws.