12V DC LED Light Bulbs are a special type of light bulb intended for solar power application, boat lighting, automotive lighting, and RV lighting. 12V DC bulbs are wired so that they can take direct current from a 12V battery and use it for illumination. If you have a solar power system and use 12V DC power in your light sockets, then these are the LED light bulbs for you. LEDs are DC powered and these bulbs have a built in DC-DC regulator to downstep the voltage to provide the right amount of power for the LEDs.
For boat lighting, automotive lighting, and RV lights, the 12V DC led bulb can be run directly from the 12V battery without the need to convert to AC power.
If you are looking at these bulbs for use in your house with 110V AC sockets...these are NOT the bulbs you are looking for. for 110V AC LED light bulbs you can look at the LED Flood lights or the LED Spot lights. WARNING: PLUGGING IN A 12V DC LED LIGHT BULB IN A 110V AC SOCKET WILL CAUSE A SHORT AND BURN OUT YOUR SOCKET AS WELL AS THE LIGHT BULB.