The OKYSTAR OKY3211-2 is a module with a tri-colour LED that uses either a LilyPad Arduino or other microcontroller. It provides a strong, bright output to create custom colours in your creations. The module has a built-in resistor to ensure safe operating voltages and can be used in a wide range of projects. It is designed for easy soldering, with a three-pin interface and two mounting holes on the back of the module. Its compact design also makes it ideal for creating space-saving and lightweight projects.