Insten Battery for 20GB iPod 4G Compatible With Apple: iPod 4th Gen. 20GB (Color Display)/30GB (Color Display)/40GB (Photo)/60GB (Color Display)/60GB (Photo). Apple iPod, iPhone, or iPad are registered trademarks of Apple, Inc. Products Keeps the music playing on your Apple iPod with this replacement battery Comes with the necessary tool to open up your iPod Voltage: 3.7 V. Dimension: 1.94 x 1.37 x 0.13" [49.28 x 34.80 x 3.30 mm]. Accessory Only. iPod not included. Charge any devices that rely on USB for power. You name it, digital cameras, high tech accessories, PDA and mobile phones, etc.