Wal-Mart unit with USB & SD card reader, plus aux. input. Love the cheap lil unit ($78), but I'm not (obviously) after anything high-end. Rear deck speakers have been replaced with 5.25", but I really wish I went with larger ones. They sound only marginally better than the cracked OEM paper speakers that have been cooking in the sun for 17 years that they replaced.
Head unit is very likeable though. Just drop some MP3's on a USB stick and plug it in. Used to have Pioneer Super Tuner III system, and absolutely loved it.
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2011 Regular Cab, 4x4 Auto, N-Fab step bars, Satoshi grille, OEM fog lights, Extang Trifecta cover (list growing, check back often!)