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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.

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

How do I file a claim on my Extend Protection Plan?

What does the Protection Plan cover?

Why would I want to purchase a protection plan for my flashlight?

Accident Protection Plan by Extend

Why does the BC21R V3 sometimes downshift to a lower output level?

Does the Fenix BC21R (V1) bike mount allow any left-right adjustment?

How can I prevent accidental activation of the BC21R V3?

Fenix BC21R V3 FAQs

Fenix Bike Lights

Are all tactical flashlights considered weapon lights?

Can I order a belt clip for my Fenix flashlight?

Can I purchase the AC and DC chargers for the Fenix RC40 flashlight?

Can I purchase the Fenix BA4C battery case?

How do the Fenix remote pressure switches function?

Can I buy a replacement holster for my Fenix flashlight?

Can I buy a replacement pocket clip for my Fenix flashlight?

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

How can I get a replacement USB port dust cover for my Fenix rechargeable flashlight?

I need a new velcro strip for my Fenix pressure switch. Where can I get one?

Fenix Accessory FAQs

How big are the Fenix 14500 batteries?

How big are the Fenix 16340 batteries?

How big are the Fenix 18650 batteries?

How big are the Fenix 26650 batteries?

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

What batteries should I use in my Fenix light?

Are ARB-L18 and ARB-L2 batteries interchangeable?

Can 14500 lithium-ion batteries be used in most other AA devices?

Can Fenix AA flashlights use Li/FeS2 batteries?

Can Fenix chargers charge unprotected 18650 cells?

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

Can I order an extra battery for the Fenix UC40UE?

Can I purchase an extra battery for the TK65R?

Can I safely use the batteries in my Fenix flashlight until they are fully drained?

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

Can my Fenix 18650 lithium-ion batteries be left in a below zero storage area for days at a time and still function when the light is needed?

Can the ARB-L18-3400 battery be charged inside the older Fenix UC30 with a USB cable?

Do I need to purchase a battery charger for the Fenix PD25's or PD25R's rechargeable battery?

Do the Fenix USB rechargeable batteries come with a charging cable?

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

Do you sell rechargeable CR123A lithium batteries?

Do Fenix batteries (Ni-MH or lithium-ion) come fully charged?

How can I tell if my battery is fully charged?

How can I tell when my Fenix USB rechargeable battery is fully charged?

How do I know when my battery is finished charging?

How long do Fenix batteries last?

How long do rechargeable lithium ion batteries last?

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

How would you compare the performance of the Ni-MH 1.2V battery and the lithium 1.5V battery?

Is the Fenix ARB-L1-2600 battery a replacement for the ARB-L1T or ARB-L1S?

Is there a recommended storage voltage for 18650 rechargeable batteries?

Is there a way to fix an overdischarged battery in deep discharge?

My Fenix battery is starting to peel and swell after charging. Is this normal?

My unit's USB port is not working. Is it covered under warranty?

Should I discharge an 18650 battery before charging it?

The plastic wrapping on my Fenix lithium-ion battery has started to tear. Is it still safe to use?

What are the advantages and disadvantages of using a micro USB rechargeable lithium-ion battery versus a rechargeable lithium-ion battery that requires a battery charger?

What are the charging requirements for batteries with charging ports?

What are the pros and cons of 18650 lithium-ion batteries?

What batteries can be charged inside USB rechargeable flashlights?

What does the mAh mean in lithium-ion batteries?

What is a protected battery?

What is the difference between the Fenix ARB-L2M batteries and the ARB-L18 batteries?

What's the difference between a $5 18650 battery and a Fenix battery?

When do I need to replace rechargeable lithium ion batteries?

Where are Fenix brand flashlights manufactured?

Where can I purchase the Fenix ARB-L2 series batteries?

Which 18650 batteries replaced the ARB-L2 series?

Which battery is better for extremely cold weather: 18650 lithium-ion batteries or CR123A lithium batteries?

Who manufactures the Fenix lithium-ion batteries?

Will a 16340 make my CR123A light brighter?

Would a standard non-Fenix AA charger charge Fenix 14500 lithium-ion batteries?

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

Can Fenix chargers charge CR123 batteries?

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

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 the Fenix ARE-X2 battery charger be plugged directly to an electrical outlet?

Can the Fenix RC40 be charged through European wall plugs?

Can the discharge feature on Fenix chargers power an iPhone?

Can you charge different types of batteries together?

Can you use AC outlet with the Fenix ARE-X11 charging kit?

Do Fenix battery chargers discharge from all bays?

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

How do I charge my Fenix 18650 battery with the ARE-X1 charger via the Micro USB charging?

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

What are things to consider when purchasing a charger?

What is the charging voltage for the Fenix battery chargers?

What is the difference between the Fenix ARE-C2+ battery charger and the older Fenix ARE C2 battery charger?

What size is the pin connector on Fenix chargers?

Why are my batteries not charging in my Fenix charger?

Fenix Charger FAQs

What is the Fenix Rewards Program and how does it work?

Can I cancel a Lumen Bucks coupon and have the points added back to my account?

Does my online account show my Lumen Bucks reward point balance?

How do I access my Fenix-Store reward points?

How do I earn Lumen Bucks reward points?

How do I redeem my Lumen Bucks rewards points?

How do I refer a friend?

What are Lumen Bucks?

What can I get with my Lumen Bucks reward points on the Fenix store?

Fenix Rewards Program

I put a fully charged 26650 battery into the Fenix PD40R (V1) flashlight and the turbo only lasted for a short while before dropping to the lower output. I can't get it back to turbo mode. Why is this happening?

Why is my PD40R not reaching the full Turbo mode?

Fenix PD40R V2 FAQS

The brightness switch on my Fenix TK16 (V1) tactical flashlight is not working. What can I do?

Fenix TK16 V2 FAQs

Fenix Flashlight FAQs

What does "IP Rating" on lights mean?

Do you have upgrades for my Fenix flashlight?

What is the color temperature of a flashlight?

Am I allowed to do modifications to my Fenix flashlight?

Are Fenix flashlights waterproof?

Are Fenix headlamps waterproof?

Are Fenix products made in the USA?

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

Can Fenix AA and AAA flashlights use Energizer lithium batteries?

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

Can Fenix flashlights take extreme temperatures like high 120 degrees?

Can Fenix headlamps attach to a baseball cap?

Can Fenix headlamps work in subzero or freezing temperatures?

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 mount my Fenix flashlight onto a shotgun?

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 power my Fenix flashlight or headlamp with non-rechargeable lithium batteries?

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

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 the Fenix E15 on a keychain?

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

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

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 you have MSDS sheets for Fenix products?

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 offer any package deals?

Do you offer discounts for military or first responders?

Do you sell bulbs for Fenix flashlights?

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

Does the APF technology in Fenix lights cause a flicker?

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 get some cool Fenix swag?

How can I order parts for my flashlight?

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

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

How do I assemble a Fenix headband?

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

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 recoil can Fenix flashlights handle when mounted on a weapon?

Is APF technology affected by magnetic fields because of a hall-effect sensor?

Is APF technology limited by current?

Is it okay to use high drain batteries in my Fenix flashlight?

Is there an extension tube attachment to increase the runtime of my Fenix light?

Is there padding to protect teeth when holding a Fenix flashlight in your mouth?

My Fenix flashlight is hot to the touch after being on turbo mode for a time. Is this normal?

My Fenix flashlight is turning on in its holster or in my pocket. What can I do?

Should I use a 5 watt or 12 watt adapter to charge my Fenix rechargeable flashlight?

Should I use a flat top battery or a button top battery in my Fenix flashlight?

What are Fenix lenses made out of?

What are the advantages of having a USB rechargeable flashlight vs. removing the batteries to charge them in a battery charger?

What are the main things to consider when selecting a flashlight?

What can I do if a battery leaks in my flashlight?

What international countries do you ship to?

What is the APF technology, how does it work, and how is it different from the hall-effect switches?

How big are the Fenix 21700 batteries?Updated a day ago