I already tried to google this but can't find an answer, first I thought it was a question clause (not sure if correct term) but then I realized there's no question word in that clause.
The sentence is from anime "kami nomi":
掃除ってレベルなのか これ 新品みたいにピカピカだぞ
I suppose the な before the なの follows the rule about distinguishing between the possession particle の because レベル is a noun. Thank you beforehand.