The IBM 02K6503 replacement laptop battery by Amstron is made from the highest quality cells and parts. The LIB-16 is designed to replace OEM part numbers: 02K6503, 02K6517, 02K6516, 02K6509, 73H9951, and 73H9861. This replacement Acer laptop battery has been rigorously tested to ensure that it is 100% compatible with the IBM ThinkPad 380/D/D-MMX/E/ED/XD/Z and 385/CD/D/D-MMX/ED/XD series of IBM notebooks. Take your work on the road with you without sacrificing performance and productivity with Amstron brand IBM laptop batteries. • Chemistry: Li-Ion • Rating: 10.8V 3600mAh • Highest quality Japanese battery cells • Will meet or exceed original specifications • Warranty: 1 Year • Not compatible with IBM Thinkpad 380CE/CS/CSE models.