"Fifteeens" refer to 15 inch subwoofers in a car audio system.
For those who don't know, that's fuckin huge. And the shit kicks.
And like a fiend fo' the weed I'll tweak.
4 Fifteens in yo' trunk that's beat,
Proper ass amps, Zapco, Alpine.
Put the coke on the dash,
roll a dolla do a line.
I'm takin' chunks from punks who want funk,
Treat em like 15's, put em in the trunk.
-Brotha Lynch Hung