Q: What kind of LED is used in TK21R?
A: One Luminus SFT90 cold white LED with a lifespan of 50,000 hours.
Q: What is the working voltage of TK21R?
A: The operating voltage is 3.0V～4.2V；The maximum operating voltage range is 3.0V～5.5V.
Q: What kind of battery can be used in TK21R?
A: 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.
Q: How to prevent accidentally activate the TK21R?
A: Unscrew the light tail cap, or remove the battery to prevent accidental activation.
Q: What are the optional accessories for TK21R?
A: 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 with GoPro interface, ALD-05 Flashlight helmet holder
Q: Why does the TK21R downshift to a lower mode after being used for a while and the higher mode cannot be selected?
A: 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 down a few lumens to reduce the temperature.
2. Low-voltage Warning
When the voltage level drops below the preset level, the flashlight is programmed to downshift to a lower brightness level until the Low mode is reached.
Q: What is the APF？
A: 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. Traditional forward switches are limited by current, and it is difficult to achieve brightness above 2000 lumens. In the age of 21700 batteries gradually expanding, 3000-lumen tactical flashlights are almost impossible with traditional circuitry, but flashlights using Fenix's APF technology can surpass these limitations!
- Make the functional tail cap simpler. Traditional multi-function tail cap needs to create a circuit through the double-layer body or additional channels but APF technology offerings a strong reliable flashlight in simple single-layer body structure.
- Better anti-interference performance. Complex external environments such as strong magnetic fields are easily resisted through stronger anti-interference ability.
Q: Why does the TK21R happen to flicker?
A: 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: Clean the contact points with a cotton swab soaked in rubbing alcohol.
