Chief Keef keeps the new music coming as he lets us hear a Mike Will Made-It produced song titled “Flex On”..Listen and download the track below. var zippywww=”94″;var zippyfile=”CLicjEBa”;var zippytext=”#000000″;var zippyback=”#e8e8e8″;var zippyplay=”#02b845″;var zippywidth=850;var zippyauto=false;var zippyvol=80;var zippywave = “#000000”;var zippyborder = “#cccccc”;