Arclyte technologies performance - lithium batteries are designed for the highly mobile user that needs extra run-time without adding more weight. They deliver outstanding performance and exceptional reliability. Expect up to 20% longer battery life per charge and more charge cycles throughout the life of the battery.Compatible with the following laptop models: MacBook Pro 17-inch 2011 version (MB604LL/A, MC024LL/A, MC226LL/A, MC725LL/A, MD311LL/A. Compatible with original/OEM part numbers: A1383.