Matching Battery: Suits perfectly for 18V BL1815 BL1820 BL1830 BL1840 BL1850 BL1860, and the batteries are not included in this E27 bulb set. Brightness: 350-1300lm. Standard Designs: The E27 12V 12W with standard threaded lamp holder also has a battery adapter, making the using and operation much easier.
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