Limited - as in it ends at 4:52 PM (PST) on Black Friday or 3:25 AM (MSK) on Cyber Monday?
Don’t need anything but people generally wish to know some sort of timeframe of a sale, for instance “until Saturday, November 30th” like @jannis presented.
Unless of course you’re going for the contrived panic approach to marketing with the absence of a timeframe to compel people to impulse panic purchase? 