21700 LI-ION battery cells perfect for power tool replacement batteries or other DIY battery building projects. 

Nominal Capacity - 4000mAh
Discharge Current - 35A Max Continuous for Cycle Life; 45A Max Continuous with 80C Temperature cutoff
Nominal Voltage - 3.6V
Max Voltage - 4.2V
Low Voltage Cutoff - 2.5V