A novel energy-saving device that uses just an empty bottle to power it is the Bottle Light for you. It's a contraption that hooks on to the mouth of a bottle; just pump the bottle a bit to create the sufficient amount of vacuum and it transforms the mechanical energy to light energy thus powering the LED lamp. The device has two modes; up and down. In the Up Mode it works like a hand torch throwing light in front of the bottle and in the Down Mode it illuminates the entire bottle. A better option than lighters and candles used at rave parties and discos.

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