BRTONG Battery for Dell Studio 15 1535 1536 1537 1555 1557 1558 Fits WU946 312-0701 WU965 KM887 Laptop Notebook Compatible Models: Dell Studio 1535 / 1536 / 1537 / 1555 / 1557 / 1558 / PP33L / PP39L Compatible part number: 312-0701 / 312-0702 / A2990667 / KM958 / KM965 / MT264 / KM904 / KM905 / MT264 / MT276 / PW773 / WU946 / WU960 / WU965 Battery type: Li-ion; Capacity: 4400mAh/49Wh; Cells: 6-cell; Voltage: 11.1V Operation time for standard batteries: Around 2 hours, the actual operation time will depend on how much electricity is required by the device and how you use it Overcharger and Discharger Circuit Protection, CE-/FCC-/RoHS-Certified for safety, About 500 recharge cycles over the life of the battery. 24 x 7 email support, 12-month hassle-free warranty