Bioserie Bioplastic Cover for iPod touch 4G (Black) Plant based bioplastic material prevents potential skin irritancy during gaming. Does not spill over the screen area, allowing easy typing, browsing, gaming and music control. Patent pending feet on the top and sides protect the screen during face down placement. Does not attract dust or stick in your pocket like silicone or rubber cases. 1 mm thick, weighs only 10 grams.