Amnergy Laptp Battery for Acer Aspire 7739 7739G 7739Z-4546 7739Z-4804 7739Z-7804 7739Z-4439; 6 Cells 5200mAh Amnergy Brand Battery Is Designed Using the Best Cells and Latest Safety Features to Work as a Perfect Replacment for the Original Battery. Guaranteed to Meet or Exceed Original Specifications. Premium Quality, 100% OEM Compatible. Brand New, Protective Retail Packaging, Each Product is Sealed with Anti-Static Shield Sleeve. Lithium Ion (Li- ion) Battery, Rechargable with No Memory Effect.