TechFuel PA3788U-1BRS New Battery for Toshiba Tecra A11-00Q A11-S3540 M11-S3430 M11-S3450 A11 M11 S11 Series - Professional 6-cell, 48Wh 10.8V Li-ion Battery Replaces Toshiba Part Numbers: PA3788U-1BRS and PABA223 Compatible with Toshiba Satellite Pro S500; Tecra A11, A11-S, M11, M11-S, and S11 Series Laptops 10.8V 4400mAh 48Wh battery constructed with advanced circuit board technology, including thermal circuit protection for safety and stability; Grade-A cells for faster charging and efficient power consumption. Precision fit construction; CE and RoHS certification ensures quality, safety and peace-of-mind. Up to 500 charge cycles. Friendly and knowledgeable Customer Support Staff available by email or toll-free telephone. No risk 30-day money back guarantee; 1-year full replacement warranty. Built with quality components and rigorous quality control. Operating time will vary depending upon computer settings, hardware use, etc. Generally, for every 2000mAh, the battery will yield approximately 1 hour of run time.