These super small LEDs are known as surface mount LEDs, SMD LEDs, or Chip LEDs.
They are very small and compact yet very bright!. The benefit of a flat and compact LED chip is that it still fives a great amount of light, but can be mounted flush, with no bulb shape showing.
These chip LEDs are wired with 8 inch red/green superfine magnet wire; no resistors needed for 3v DC operation.
Package includes one (1) prewired LED.
For more types of LEDs, see our friends at Model Train Software