NOTE: For iPhone 3G only, NOT compatible with iPhone 1st generation Keep the music playing on your iPhone with this back-up battery Keep one handy for those times when there are no outlets to charge your iPhone 3G External Rechargeable Li-Ion Battery Pack for Apple iPhone 3G Includes a transparent white silicone skin On / Off power switch LED power indicator Battery Type: Lithium-ion Cell This backup battery is able to be recharged with the iPod charging cable or charger (Charger and Charging cable is avaliable for purchase separately) Output Voltage 5.5V User Manual Included Color: Black Compatible with: Apple iPhone 3G ONLY.