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<p style="text-align: justify;"><span style="color: rgb(0, 0, 0);">The dimensions of the Fenix ARB-L21 series 21700 battery are 76mm x 21.5mm (.85&quot; x 2.99&quot;). It&apos;s a powerful, protected cell compatible with many current Fenix flashlights and headlamps.</span></p>

The dimensions of the Fenix ARB-L21 series 21700 battery are 76mm x 21.5mm (.85" x 2.99"). It's a powerful, protected cell compatible with many current Fenix flashlights and headlamps.

How big are the Fenix 21700 batteries?

Fenix Battery FAQs

Am I allowed to do modifications to my Fenix flashlight?

Are all tactical flashlights considered weapon lights?

Are Fenix flashlights waterproof?

Are Fenix headlamps waterproof?

Are Fenix products made in the USA?

Are there any Fenix flashlights for mining, industrial work, or other hazardous environments?

Are there any Fenix flashlights with a TIR lens?

Are there any retailers who carry Fenix flashlights?

Are there instructions on how to take apart my Fenix flashlight?

Batteries leaked or corroded in my Fenix flashlight. What should I do?

Can a 16340 battery be used in place of a CR123A battery?

Can a USB rechargeable battery be charged in a Fenix USB rechargeable flashlight?

Can Fenix AA and AAA flashlights use Energizer lithium batteries?

Can Fenix AA flashlights use Li/FeS2 batteries?

Can Fenix flashlights take extreme temperatures like high 120 degrees?

Can Fenix headlamps work in subzero or freezing temperatures?

Can Fenix USB rechargeable flashlights, headlamps, bike lights, and batteries be charged using a computer USB port?

Can I change the bulb in my Fenix flashlight?

Can I charge an unprotected battery in a Fenix rechargeabe flashlight, headlamp, or bike light?

Can I leave my Fenix rechargeable flashlight plugged in all the time?

Can I mount my Fenix flashlight onto a shotgun?

Can I order a belt clip for my Fenix flashlight?

Can I order a new tail switch rubber boot cover for my Fenix flashlight?

Can I order a two-way pocket clip for my Fenix flashlight?

Can I purchase a more powerful battery for my Fenix HL40R headlamp than the 2000mAh battery it comes with?

Can I purchase a tail cap or a tail switch for my Fenix flashlight?

Can I purchase o-rings for my Fenix flashlight?

Can I recharge my USB rechargeable flashlight using a USB charger for my iPhone or iPad?

Can I register multiple Fenix lights using a single e-mail?

Can I remove the strike bezel on my Fenix flashlight and still use the flashlight?

Can I switch the tail caps of one Fenix flashlight with another?

Can I upgrade any internal components of my older Fenix flashlight with a newer version?

Can I upgrade or trade-in my old or discontinued unit to a current model?

Can I use a USB AC adapter with a Fenix USB rechargeable flashlight or Fenix charger?

Can I use any 18650 battery in my Fenix flashlight?

Can I use Duracell batteries in my Fenix flashlight?

Can I use rechargeable RC123A batteries in Fenix lights?

Can I use Samsung batteries in Fenix lights?

Can I use unprotected 18650 lithium-ion batteries in my Fenix flashlight, headlamp, or bike light?

Can the discharge feature on Fenix chargers power an iPhone?

Can the Fenix HL35 headlamp be tilted up or down or is the headlamp locked in place?

Can the top portion of the headband be removed and re-installed on Fenix headlamps?

Can you upgrade the battery included with a flashlight to a battery with higher milliamps?

Do any Fenix bike lights fit on the vertical bar?

Do Fenix 18650 lithium ion batteries work in other non-Fenix devices?

Do Fenix flashlights come with batteries?

Do Fenix flashlights have glass lenses?

Do Fenix flashlights have parasitic drain?

Do Fenix flashlights have reverse polarity protection?

Do Fenix flashlights that use APF technology require a mechanical tail switch, electronic side switch, or rotary switch?

Do Fenix flashlights use CREE LED bulbs?

Do Fenix flashlights, headlamps, or bike lights work with Nitecore batteries?

Do I have to recharge the batteries in my Fenix rechargeable flashlight or can I use a battery charger?

Do the batteries in my rechargeable flashlight have to be charged through the flashlight or can I use a battery charger?

Do you carry tactical flashlights that feature a red light?

Do you have a Fenix battery charger for the Fenix ARB-L26-4500P battery?

Do you have a Fenix flashlight that is considered intrinsically safe?

Do you have a Fenix flashlight with an infrared beam?

Do you have a flashing front or back Fenix light for bikes?

Do you have a flashlight that features an adjustable focus, is rechargeable, and has a good LED?

Do you have a headlamp with a single function or output?

Do you have a rubber headband or strap to help keep my Fenix headlamp on my hat?

Do you have a small Fenix flashlight with a red beam?

Do you have alternate pocket clips for Fenix flashlights?

Do you have any Fenix bike lights that run on AA batteries?

Do you have any Fenix flashlights with an adjustable focus?

Do you have any open-box, refurbished, or returned Fenix flashlights, headlamps, bike lights, and accessories?

Do you have discounts during Black Friday?

Do you have MSDS sheets for Fenix products?

Do you have upgrades for my Fenix flashlight?

Do you offer any package deals?

Do you offer discounts for military or first responders?

Do you sell belt holsters for my Fenix flashlight?

Do you sell bulbs for Fenix flashlights?

Do you sell micro USB charging cables?

Do you sell rechargeable CR123A lithium batteries?

Do you sell replacement brackets for Fenix headlamps?

Does APF allow Fenix lights to be brighter than 2200 lumens?

Does Fenix make a headlamp that has different colored LEDs such as red, green, blue?

Does Fenix make a headlamp with a red LED that has more than one lumen?

Does Fenix offer any flashlights for marine or diving use?

Does the APF technology in Fenix lights cause a flicker?

Does the Fenix 26650 battery fit inside a Fenix PD35 (V1), PD35 V2.0, or PD35 TAC flashlight?

What is the color temperature of my flashlight?

Which flashlights can be weapon mounted?

Does the heat protection on Fenix flashlights react to the actual temperature of the flashlight or is based on a built-in timer?

How can I be sure I'm purchasing a genuine Fenix product?

How can I fix the button or tail switch on my flashlight?

How can I order parts for my flashlight?

How can I request a donation for my charity or event?

How can I get some cool Fenix swag?

How can I tell how long a battery will last in my flashlight?

How do I know when my battery is finished charging?

How do I register my Fenix flashlight, headlamp, or bike light?

How do I assemble a Fenix headband?

How do I remove the pocket clip on a Fenix flashlight without hurting the flashlight or clip?

How do I select a headlamp? So many choices!

How do I write a review about my Fenix purchase?

How do the different button and switches work on my Fenix flashlight?

How much longer would a Fenix flashlight run if I were to use an 18650 3500mAh battery vs an 18650 2600mAh battery?

General FAQs

Are Fenix chargers compatible with non-USA sockets?

Can Fenix chargers charge CR123 batteries?

Can Fenix chargers charge the ARB-L18-2600U and ARB-L18-3500U batteries?

Can Fenix chargers charge unprotected 18650 cells?

Can I charge Fenix USB rechargeable 18650 batteries using a battery charger?

Can I charge non-Fenix batteries in my Fenix battery charger?

Can I leave a fully charged lithium-ion battery in an unplugged Fenix charger?

Can I leave my rechargeable flashlight or battery plugged in all the time?

Can you charge different types of batteries together?

Do Fenix battery chargers discharge from all bays?

Do Fenix chargers include non-USA plugs?

Does the Fenix ARE-A4 charger plug into a regular 120 volt outlet?

How does the discharge function work on my Fenix battery charger?

How long does it take to charge a Fenix battery in a Fenix charger?

I lost the AC cable for my Fenix charger. Can I purchase a replacement?

Is there a Fenix charger that will charge AA Ni-MH batteries?

What are things to consider when purchasing a charger?

What does the Limited Lifetime Warranty Cover?

What is the charging voltage for the Fenix battery chargers?

What size is the pin connector on Fenix chargers?

Which Fenix battery chargers can charge 14500 batteries?

Which Fenix battery chargers can charge 26650 batteries?

Which Fenix battery chargers can charge a 16340 battery?

Which Fenix battery chargers can charge a 21700 battery?

Which Fenix battery chargers can charge Ni-MH / Ni-Cd batteries?

Which Fenix battery chargers charge 18650 lithium-ion batteries?

Why are my batteries not charging in my Fenix charger?

Will the Fenix ARE-A4 charger work with the 18650 batteries used in my Fenix TK35UE flashlight?

Fenix Charger FAQs

What batteries can be used in the BC26R?

What is the color temperature and working voltage of the BC26R?

Does the BC26R have a lockout function?

Fenix BC26R FAQs

How long does it take to charge the Fenix C7?

What is the color temperature and working voltage of the C7?

Is the charging port of the C7 waterproof?

Does the C7 have overheat protection?

What batteries can be used in the C7?

Does the C7 have a lockout funciton?

Fenix C7 FAQs

Why is the E-Spark not charging my phone?

How do I activate the discharge on the E-Spark?

Does the E-Spark have a lockout function?

The E-SPARK uses a white and red LED with international patents that comply with IES LM-80 standards. They have a lifespan of 50,000 hours  Did this answer your question?   Last updated on September 19, 2022 Search Toggle Search

How much can the E-SPARK charge my phone?

Is the E-Spark rechargeable?

Fenix E-SPARK FAQs

Is the GL22 Rechargeable

Can the GL19R battery indicator be turned off?

Fenix GL19R FAQs

What type of pistols does the GL22 fit?

What kind of battery does the GL22 use?

Does the GL22 feature a lockout function?

Why does the GL22 output drop on its own?

What is the color temperature and working voltage of the GL22?

Fenix GL22 FAQs

How long does it take to recharge the HM70R headlamp?

Why does the HM70R downshift to a lower output mode?

Is the charging port of the HM70R waterproof?

Fenix HM70R FAQs

Does the T6 feature a lockout function?

What battery can be used in the T6?

What LED is used in the Fenix T6?

What type of ink cartridge is used in the T6 Penlight?

What is the color temperature and working voltage of the T6?

Is the T6 Rechargeable?

Fenix T6 FAQs

Is the WT25R rechargeable?

What is the adjustable angle of the WT25R head?

What batteries can be used in the WT25R?

Does the WT25R have overheat protection?

Fenix WT25R FAQs

Can you purchase extra mounts for Fenix bike lights?

How long does it take to charge the Fenix BC05R V2 taillight?

Is there a white version of the Fenix BC05R bike light?

What batteries work in the Fenix BC05R bike light?

What else can the BC05R Tail Light be used for?

Which battery chargers will work with the Fenix BC05R batteries?

Fenix BC05R V2 FAQs

Does the ALB-10 bike mount work with the Fenix BC21R (V1) bike light?

Is there a screw or clamp fixing mount that is compatible with the Fenix BC21R (V1) bike light?

How big are the Fenix 21700 batteries?Updated 5 hours ago