Fenix Rechargeable 4000mAh 21700

The all-new Fenix rechargeable 21700 battery is designed for large current output. The maximum current for the ARB-L21-4000P is 18A, with a continuous output current of 10A. Why is this necessary? The higher current allows the 21700 battery longer runtimes in flashlights. As with all Fenix rechargeable batteries, the 21700 4000mAH has three sets of overheat protection, including pressure relief, microporous, and PTC cathodal block. The pressure relief vents all gas to be expelled; this prevents secondary hazards. 
Specifications

Type - ARB-L21-4000P
Capacity - 4000mAh
Voltage - 3.6V
Charging Current 1A Recommended, 4A Maximum
Max Output Current - 18A (Less than 3 Minutes)
Max Continuous Current - 10A
Weight - 2.47 Ounces 
Dimensions - 2.99" Height x 0.85" Diameter
Warranty - 12 Months Free warranty from date of purchase

***Batteries purchased without any equipment they can operate must be shipped with ground shipping. If you purchase only batteries and no flashlights/headlamps you must select UPS/Fedex Ground unless your order meets the free shipping threshold.***