100pcs 5mm RGB Slow Flashing LED Diodes Multicolor (Colors Changed Automatically) Flat Lens (DC 3V) +100pcs Resistors (for DC 6-12V), Bulb Lamps Light Emitting Diode

These are nice, bright, inexpensive color changing LEDs. I've used mine to make USB powered, rectangular grid decorative lights, and they work quite splendidly. A note for other potential buyers though: cheap color changing LEDs like this WILL NOT remain synchronized for more than one or two cycles. If you need color changing LEDs to synchronize, you have to get ones designed specifically for that feature (if they exist), or get RGB LEDs and control them using a micro-controller or some other similar method.

I put one of these diodes on a lab power supply set at 3 volts for six hours. At that voltage, it consumes 14ma of current and is VERY bright. After six hours there are no problems, the current is dead on steady, and it is just warm, not hot. I conclude 3 volts is a good setting for this LED. The calculation for finding the current limiting resistor desired ( a resistor in series with the LED) for this 3 volt LED at 14ma is simple,( using a battery also in series). Here are examples: R =(Battery voltage - LED voltage )/ Led Current in amps For a 6 volt battery: R = 6-3/0.14 = 214 ohms For a 12 volt battery: R = 12-3/0.14 = 642 ohms Note that resistors do not come in every value, so choose the next larger one. For a 1% tolerance resistor, use 215 ohms and 649 for the above. For a 5% tolerance resistor, use 220 ohm and 680 ohm. The enclosed 430 volt resistors works well with a 10 volt power supply. Five bucks for a hundred (5c each) seems like a bargain.

They work great using two AA batteries

I find that these LEDs work very well , the colors are good. The warm white is very nice. Can recommend these. Thanks

This is about the 3mm warm white LEDs. I'm using these as replacements for lamps in an audio meter, and don't really need all of the brightness these small LEDs have to offer. In my application, using the included 430 ohm resistors provided too much light, so I went with a higher value resistor from my supply in order to dim them a bit. They're running fine on the low-voltage AC (sic) that the meter provides. Depending on your supply voltage, which would likely be DC, 430 ohms might just right. I only needed a few LEDs, but for the price, I'll be fine having a lot of these on hand for future projects.

i sued them to make spiderman invitaions for my sons birthday party and they were east so use. i used them with copper tape.

The work great. You need to use the resistor included with it or you will burn it out in minutes. Like the other reviews have said. Super cool they include the resistor too. I’m going to be making a dome light with this for my car. I cranked it up to 21.9 volts just to see how long it would run. It’s been going for hours now

Nice variety pack of LEDs for automobile

Excelentes, solo que el de 3mm mide en realidad 3.180 mm (de acuerdo a medicion hecha con un vernier)

Excelente leds projects .

Funcionaron perfectos para remplazos de un árbol con luces integradas