Fenix TK17 Reference Manual and SpecificationsUpdated 2 hours ago

The Fenix TK17 is a dual switch tactical flashlight. This summary is drawn from the manufacturer's official user manual — see the downloadable PDF reference manual on the product page for complete details.

Warning

Do not look directly at the light source, stare at the light spot, or shine the light directly into the eyes of anyone.
Do not disassemble the light unless you are a professional.
Do not place this light within reach of children.
Do not place the light head near flammable objects; high temperatures can cause objects to overheat and become flammable/ignite.
Do not use the light in inappropriate ways such as holding the unit in your mouth — doing so could cause serious personal injury or death if the light or internal battery fails.
This light will accumulate a significant amount of heat while operating, resulting in a high temperature of the light shell. Pay close attention to avoid burns.
Turn off the light or remove the battery to prevent accidental activation when the light is placed in a closed, flammable environment such as pockets and backpacks.
The LED of this light is not replaceable; the whole light should be replaced when the LED reaches the end of its lifespan.

Product Features

3600 lumens maximum output, 330 meters maximum beam distance
Includes a Fenix ARB-L21-6000B battery with a two-way USB-C port for charging and discharging
Dual tactical tail switch for instant burst and instant strobe
Internal dual-spring structure ensures stable lighting even under severe impact
Battery level indicator on the tail cap
Stainless steel strike bezel inlaid with three tungsten steel breaking tips
Made of durable A6061-T6 aluminum alloy, with a hard-anodized light body and titanium-coated body clip
Size: 5.85'' x 1.42'' x 1.00'' / 148.5 x 36 x 25.4 mm. Weight: 6.96 oz / 197.2 g (including battery)

Operating Instructions

On/Off: tap the tactical switch to turn on the light silently; release it and the light will go out. Fully press the tactical switch to constantly turn the light on/off.

Output Selection: with the light switched on, single click the functional switch to cycle through Low, Med, High, and Burst.

Instant Burst: fully press the tactical switch for 0.5 seconds to enter Burst and lock this output; tap the tactical switch or functional switch to recall the previously used output.

Strobe Mode: with the light switched off, tap the functional switch to enter Strobe; release it and the light will go out. With the light switched on, press and hold the functional switch for 0.5 seconds to enter Strobe; tap the functional switch or tactical switch again to exit Strobe and recall the previously used output, or fully press the tactical switch to turn the light off.

Intelligent Memory Circuit: the light automatically memorizes the last selected output, excluding Strobe. When turned on again, the previously used output will be recalled.

Technical Parameters (ANSI/PLATO FL1)

Burst: Output 3600 lumens, Runtime 3 h 45 min*, Distance 330 meters, Intensity 27,300 cd.
High: Output 1000 lumens, Runtime 3 h 50 min, Distance 170 meters, Intensity 7,250 cd.
Med: Output 350 lumens, Runtime 8 h, Distance 100 meters, Intensity 2,450 cd.
Low: Output 30 lumens, Runtime 60 h, Distance 30 meters, Intensity 225 cd.
Strobe: Output 3000 lumens.

Impact Resistance: 1 meter | Water Resistant: IP68

Note: according to the ANSI/PLATO FL1 standard, the above specifications are from the results produced by Fenix through its laboratory testing using one Fenix ARB-L21-6000B battery under the temperature of 21±3°C and humidity of 50%-80%; the true performance of this product may vary according to different working environments and the actual battery used. *The Burst output is measured in total of runtime including output at reduced levels due to temperature or the protection mechanism in the design.

Battery Specifications

Fenix ARB-L21-6000B (21700, 3.6V): Recommended.
Fenix ARB-L21-6000 (21700, 3.6V): Recommended.
Fenix ARB-L21-5000 V2.0 (21700, 3.6V): Recommended.
Fenix ARB-L21-5000U (21700, 3.6V): Recommended.
Fenix ARB-L21-4000P (21700, 3.6V): Recommended.

It is strictly prohibited to use an 18650, CR123A, or 16340 battery. 21700 Li-ion batteries are powerful cells designed for commercial applications and must be treated with caution and handled with care. Using low-quality batteries or mishandling batteries (such as short-circuiting or overheating) could lead to combustion and jeopardize the safety of users and property; any adverse effects from low-quality batteries are not covered by any Fenix warranty or liability. Using quality batteries with circuit protection will reduce the potential for combustion or explosion.

Battery Replacement: unscrew the light tail to insert the battery with the anode side (+) towards the light head, then screw the light tail back on.

Charging

Loosen the light neck or tail cap to remove the battery, then connect the USB Type-C end of the charging cable to the battery.
The three indicators on the battery will display blue while charging, and the number of constant-on indicators shows the current battery level. All three indicators stay constant-on once charging is complete.

Note: recharge the battery of a stored light every four months to maintain optimum battery performance.

Battery Level Indication

Press either switch to turn on the light and turn it off within 1 second; after 0.5 seconds, the battery level indicator will show the battery level and will last for 3 seconds.
The indicator remains off if the light stays on for more than 1 second, or if the light is currently on.
While the indicator is on, press either switch to turn off the indicator and turn on the light.
Green light on: saturated, 100% - 85%.
Green light flashes: sufficient, 85% - 50%.
Red light on: poor, 50% - 25%.
Red light flashes: critical, 25% - 1%.

*This only works with a Fenix ARB-L21 series 21700 rechargeable battery.

Low-Voltage Warning

When the voltage level drops below the preset level, the light is programmed to downshift to a lower brightness level. When the voltage level is still too low, the flashlight blinks 3 times every 5 seconds to remind users to replace or recharge the battery. This only works with a Fenix ARB-L21 series 21700 rechargeable battery.

Intelligent Overheat Protection

The light will accumulate a lot of heat when used at high output levels for extended periods. When the light reaches a temperature of 60°C/140°F or above, it will automatically step down a few lumens to reduce the temperature. When the temperature drops below 60°C/140°F, the light will gradually recall the preset output level.

Usage and Maintenance

Disassembling the sealed head can cause damage to the light and will void the warranty.
Fenix recommends using an excellent-quality battery.
If the light will not be used for an extended period, remove the battery, or the light could be damaged by electrolyte leakage.
Loosen the tail cap or take out the battery to prevent accidental activation during storage or transportation.
Long-term use can result in O-ring wear; to maintain a proper water seal, replace the ring with an approved spare.
Periodic cleaning of the light and battery contacts improves the light's performance, since dirty contacts may cause flickering, intermittent operation, or failure to illuminate.

What's Included

Fenix TK17 flashlight, ARB-L21-6000B battery, Type-A to Type-C charging cable, Type-C to Type-C charging cable, Holster, Lanyard, 2 x Spare O-rings, User manual, Warranty card.

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