Replacement Battery for Microsoft Zune 2nd 16G/32G/64G, DOCA 3.7V Rechargeable Battery with Opening Pry Tool Kits - Compatible for Zune 2nd HD Voltage: 3.7 V, Capacity: 700mAh , up to 30 hours of usage. Li-Polymer Rechargeable Battery for Microsoft Zune HD. 16GB/ 32GB /64GB Models. It is easy to install the battery by using Opening Pry Tool Kits. Please verify your Zune model so that you are certain to purchase the correct parts. We provide 12 months worry-free return warranty and lifetime friendly, please feel free to contact us if you have any question.