Pairs of pre-wired LEDs in the collowing sizes and colors:
 
Two pre-wired 0402 LEDs in your choice of bright-white, warm-white, red or green. 
 
Two pre-wired 0805 LEDs in warm-white. (the LEDs included in the E/F-unit kits)
 
Two pre-wired 1206 LEDs in warm-white. (the LEDs included in the Conversion Kits)