Fenix TK21R FAQs

What is the working voltage of TK21R?

The operating voltage is 3.0V～4.2V；The maximum operating voltage range is 3.0V～5.5V.

What kind of LED is used in TK21R?

One Luminus SFT90 cold white LED with a lifespan of 50,000 hours.

What kind of battery can be used in TK21R?

It is recommended to use a Fenix 21700 Li-ion battery. Other Li-ion batteries are not recommended. As an unmatched battery may cause the flashlight to fail to work normally.

How to prevent accidentally activate the TK21R?

Unscrew the light tail cap, or remove the battery to prevent accidental activation.

AOT-04 Traffic wand, ALG-00 Rail mount, ALG-15 Rail mount, ALG-16 Rail mount, ALG-18 Flashlight ring, AER-05 Remote pressure switch, ALP-10L Flashlight holster, ALP-20 Quick-pull holster, ALR-01 Tactical flashlight ring, ALB-10 Bicycle light holder w

Why does the TK21R downshift to a lower mode after being used for a while and the higher mode cannot be selected?

There are two reasons:. 1. Intelligent Overheat Protection. The flashlight will accumulate a lot of heat when used at high output levels for extended periods. When the light reaches a temperature of 55°C or above, the light will automatically step do

What is the APF？

The APF (Advanced Pulse-Frequency Transmission System) was developed by Fenix laboratory, a major technology breakthrough of flashlight industry. Allowing the tactical flashlight to achieve a higher level of performance:. Take light to the extreme. T

Why does the TK21R happen to flicker?

The reasons that may cause the light to flicker, shine intermittently or even fail to illuminate:. 1. Poor battery level. Solution: Recharge or replace the battery. 2. The contact or contact point of the battery or flashlight is dirty. Solution: Clea