42mm 578 LED Car Bulbs

Amazing. The stock halogen lighting in my car is very, very dim and I wanted to upgrade, but didn't want to pay a lot. After reading a lot of reviews, I chose this one and I must say that the other reviews are right - These things are BRIGHT! I could easily read a book with just one overhead bulb without eye strain. They are very cool white - Not bluish, but just very sterile, clinically pure white (which I like). If you want the warm, yellowy 'halogen-like' light, these are not for you. The price is fantastic for 4 bulbs, so I have lots of spares in case they start flickering (which a lot of reviews for other products mention). I can't speak to their longevity since I just received them. What's nice is that it is an array of 48 LEDs, so if one or a few of them die, it will be barely noticeable, wereas these LED bulbs with just a few (or one) high-powered LEDs will have a significant drop in output if one or more of the LEDs die. Ironically, these bulbs draw approximately the same amount of power (3.8W / 317mA) as the halogen festoon bulbs they replace. BUT instead of the puny 50 lumens the halogen bulbs put out, these put out several times that (I don't have a light meter, but my guess is around 400 lumens). I can't speak to CAN bus compatibility because my car doesn't use that. One final point - I personally feel that these are really only for the overhead (dome) light - They are just too bright for footwells, etc. Just one bulb makes the whole interior look like daylight. Three would be crazy overkill - Maybe even unpleasant. But if you have a really small, poorly designed dim bulb fixture, then this will fix that and make it look like there is a 40-watt bulb in your car.

Perfect fit bright led light. Highly recommended.

Very pleased with the brightness and color. It transformed my RV's driver cabin which had a ultra low lumen halogen bulb. Could not even see the steering wheel with that light, now it is much better. I had to buy a 578 bulb holder and stick it into the dome light casing.

These bulbs are super bright and two will make it look like daylight inside my 2005 4-door Dodge Ram (same as 2002-2008). The problem is that they won't work correctly in all sockets/applications. I will explain - My Ram has a dome light, two map lights, and a glove box light in the cab. These will work in the dome light correctly, but not the others. The map lights won't come on by using the switches, only when a door is opened (not acceptable). In searching the web, I found that this is because of the CAN bus system installed in most modern cars. If you google "Using LED with a CAN Bus System", it will come up. What I did to make these work well enough for now is to install an old conventional bulb in the left map light and an led in the right one. That way, when I open the doors, the dome light and map lights come on as intended. When I need a map light, I have to turn on the left one FIRST (old bulb), and if I want more light, then turn on the right one (led). The only way the glove box led will come on is if the left map light is on as well. I rated these bulbs 5 stars because they're so dang bright, and it's kinda my fault for not knowing I needed the CAN bus leds. Now I'll check into the price of error-free CAN bus compliant leds... If you want to read what others here said about this error, do a search thru these reviews for "canbus".

I got these to replace the bulbs in the ceiling light fixtures of my camper. They're extremely bright -- 800 lumens makes them equivalent to a 60 watt incandescent bulb, at least in theory. With all that light in such a small space, they're kind of painful to look at directly -- you'll want to use them in a fixture with some kind of diffuser. The light color is white, very close to daylight to my eyes. They were slightly too long for the clips in my fixtures, which are supposed to take a 211-2 festoon bulb. I think the problem is with glass bulbs it didn't matter if they were a little too close together, but with these the protruding circuit board makes it more critical. I was able to make it work by angling them a little. The current-limiting resistors are in one end cap and get really hot. It's less heat overall than an incandescent bulb would make, but enough to burn your fingers when it's concentrated in one place like that. I'm a little concerned that the heat will cause the components to fail prematurely, but only time will tell.

Very bright little LED bulbs. So far they seem to be of good quality so I hope they last a long time.

I got these to replace the halogen bulbs on my 1999 SeaRay 400 Sundancer boat. The price was good and they shipped to me in one day. I will buy again for sure. They are also much brighter than the original bulbs and are much cooler, not to mention use less energy to run. Highly recommend, I will update should the bulbs fail prematurely. Update: 10-11-2023: I ordered these again because I was so impressed with the quality and brightness.

I used the 3 LED bulbs to replace the overhead factory map and dome lights in my car. The LED lights worked perfectly and were brighter than the stock non-LED lights that came with the car. I watched a video on YouTube first, to get an idea of how to remove the dome light fixture so that I could install the LED bulbs. I've only had the LED lights in my car for one week but so far so good. So even though I rated the Longevity at 5-Stars, I am assuming they will last a long time because the LED bulbs look well made and have a good heat sink to protect the electronics.