The Rambam Writes in Hilchos Channukah Perek 4 Halacha 12
אפילו אין לו מה יאכל אלא מן הצדקה שואל או מוכר כסותו ולוקח שמן ונרות ומדליק
What is the reason why the Rambam wrotes to take “Shemen and Neros” to light. Seemingly he could have just written “Shemen” or “Neros”.
There is the “famous” shita of the Evnei Nezer that there is a din “cli” by the Channukah candles (See Chelek Beis Siman 500.) However perhaps this Rambam is coming to also say that one needs to use a cli davka? Why wouldn’t it have sufficed to use just the word “shemen” or “neros”.
The shemen is the oil, and the neros are the cups to hold the oil. One can’t have one without the other.
I don’t see so much beyond this in the words of the Rambam.