After-hours buzz: Mattress Firm, FleetCor & more By: CNBC.com News June 09, 2015 at 17:36 PM EDT Check out the companies making headlines after the bell Tuesday: Mattress Firm, FleetCor, Gulfport & more. Read More >> Related Stocks: Fleetcor Technologies GX Defense Tech ETF Greif Bros Corp Gulfport Energy Corp Prudential Financial Target Corp