Got a GU10 bulb that needs replacingAre you scratching your brain trying to find out what the heck GU10 bulbs are Well, I'm no light bulb expert, but I spent the past forty-five minutes trying to find this out, and I couldn't find any easy answers. On the plus side, I'm now a semi-expert on a variety of related light-bulb topics, including GU10 bulbs, LED bulbs, incandescent bulbs, the benefits of Sylvania, spot lights versus floodlights, and halogen lights! So I decided to write this article so that hopefully you, the GU10 bulb-curious reader, won't have perform the same lengthy research that I did.What GU10 Stands ForFirst of all GU10 bulbs is a bit of a misnomer, since the description GU10 actually describes the light bulb's base. That is, the part of the bulb that plugs into the socket, or mount, or light fixture, or whatever you have set up to deliver power to your light bulbs.What's DifferentA GU10 bulb base is not threaded, like a conventional light bulb. Rather, it is what they call a bayonet mount. A bayonet mount is a light bulb base consisting of interlocking slots and pins. The letters GU tell us that the base has a bipin cap, meaning that it has two pins (the male end of the connection) on the end of the light bulb. The number 10 tells us the diameter of the base in millimeters; so a GU10 bulb has a base cap that is 10 mm in diameter.The pins themselves aren't just metal prongs, but have a little cylinder connected to the end of them. This cylinder is bigger than the prong that connects it to the base; so one of the things you have to watch out for, when you're installing GU10 bulbs, is making sure that the cylinder slides neatly into the socket. Another tip is that when you're removing the bulb, you have to press the bulb into the fixture a little bit to trigger the spring, releasing the bulb; then, twist about a quarter-turn counterclockwise.Other VariablesI've learned that GU10 bulbs are usually quartz/halogen-type lights, but can also be LED (light-emitting diode) in nature. LED light bulbs, of course, have some notable advantages over incandescent light bulbs. First, LED light bulbs last much, much longer; 100,000 hours or so for an LED bulb compared to only about 5,000 hours for an incandescent bulb. The great benefit to this vastly increased lifespan is that if your bulb is located in an inaccessible spot-such as on the ceiling, high up on the wall, or outside somewhere-then using an LED bulb greatly reduces how often you will need to replace that inconvenient bulb. Notably, LED light bulbs are also estimated to be about four times more efficient than incandescent bulbs, due to less of the energy being lost as heat.So if you're looking for a replacement to your GU10 bulb, I would recommend going the LED route, if possible. You'll save money in the long run.