Please Note: Products are designed and rated for use in the United States using 120 volt current. With or without a transformer, this product is not recommended for use outside the US. These 11" Bamboo Barrel Light Set (10 Lights) are made of wood. Each light has a replacable bulb. Light string measures 11" in length with 10 lights attached. White power cord is UL listed. Has end to end plug to attach more light strands (other strands are sold separately). Can be used indoors or out. Includes 4 extra bulbs. Please Note: Lights burn steady on and do not flash.