Review on CHANZON 100Pcs (10 Colors X 10Pcs) 3Mm LED Diode Lights Assortment (Clear Transparent Lens) Emitting Lighting Bulb Lamp Assorted Kit Variety Colour Warm White Red Yellow Green Blue Orange UV Pink by Madison Dickinson

I wanted to put RGB LEDs on a badge (Sparkfun's very cool little Day of the Geek--check it out at sparkfun dot com) rather than settle for single color lamps. Using a microprocessor with associated power supply and circuitry would be grossly impractical. Fortunately, these Chanzon slow fading LEDs are the perfect solution. It's remarkable how well they stay in sync, though as you might correctly assume: In the absence of external control this will be far from exact. Still, in this or similar applications they are ideal.