10440 Batteries
Rechargeable 10440 Batteries are lithium-ion cells the same size as AAA batteries but with higher 3.7V output for powerful compact flashlights. These quality flashlight batteries deliver consistent performance through hundreds of charge cycles for smaller EDC lights and keychain lights.
Is a 10440 right for your light?
A 10440 is a small cell, so it trades runtime for power in a tiny package. That makes it a fit for compact, high-output EDC lights that need more current than a standard AAA can give, and it recharges instead of getting tossed after one use.
The catch is voltage. At 3.7 volts a 10440 runs far higher than the 1.5-volt AAA it resembles, and dropping one into a light not rated for it can damage the light, so confirm your flashlight lists 10440 support before using one.