rearlight

i have a o2 400 ex im rebuilding. im sure it came factory with some sort or rear light but ther is nothing. would it be a bral and tail or just tail? if so what colors of wires would i look for and were would they be? thanks also i just bought a durablue axel used. how can i be sure it is a real durablue? i dont see any stamp or anythanks. thanks for any halp