Fenix E40R Reference ManualUpdated an hour ago

The Fenix E40R is a high-output rechargeable EDC 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.

Overview

The E40R delivers up to 5000 lumens maximum output and 242 meters maximum beam distance from four high-performance 6500K LEDs rated for a 50,000-hour lifespan each, powered by an included ARB-L21-5500 21700 battery with fast USB Type-C charging.

5000 lumens maximum output, 242 meters maximum beam distance.
Four high-performance 6500K LEDs, 50,000-hour lifespan each.
Included ARB-L21-5500 battery provides a max runtime of 89.5 hours in Eco mode.
Combined spotlight/floodlight output for wide coverage.
Toggle switch manages lockout, activation, and Turbo; electronic switch handles output selection and Strobe.
Lockout function prevents accidental activation.
USB Type-C fast charging — 1.5 hours from depleted to full.
Magnetic tail and included body clip.
Ring-shaped battery indicator with low-battery warning.
Reverse polarity protection.
Waterproofed USB Type-C port with silicone dust plug.
Made of high-strength, oxidation-resistant A6061-T6 aluminum. IP68-rated.
Size: 5.43" x 1.38" x 1.04" / 138 x 35 x 26.4 mm.
Weight: 5.15 oz / 146 g (excluding battery); 7.76 oz / 220 g (including battery).

Operating Instructions

On/Off: Turn the toggle switch from Lockout to General mode to turn on; back to Lockout to turn off. In General mode, press and hold the electronic switch for 0.5 seconds to turn on/off.

Mode Switching: Turn the toggle switch to cycle bidirectionally through Lockout ↔ General ↔ Turbo.

General Mode: Single click the electronic switch to cycle Eco → Low → Med → High; press and hold 1.2 seconds to enter Strobe.

Turbo Mode: Keep pushing the toggle switch to enter Turbo; release to return to General mode.

Intelligent Memory Circuit: Memorizes the last General mode output; activates in Med if previously switched off in High.

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

Charging

Open the anti-dust plug and connect the USB Type-C end of the charging cable. The indicator displays red while charging and turns green when full; close the anti-dust plug after. The flashlight can be operated while charging. Normal charging time is about 1.5 hours with a 9V/3A adapter. Recharge a stored flashlight every four months.

Battery Level Indication

Green on: saturated 100–85%. Green flashes: sufficient 85–50%. Red on: poor 50–25%. Red flashes: critical 25–1%. Works only with a Fenix ARB-L21 Series battery.

Intelligent Overheat Protection

At 60°C/140°F or above, the flashlight automatically steps down output to reduce temperature, gradually recalling the preset output level as it cools.

Low-Voltage Warning

Below the preset voltage level, the flashlight downshifts until Eco is reached and blinks red to prompt recharging. Below 2.8V, over-discharge protection automatically turns the light off to protect the battery.

Technical Parameters (ANSI/PLATO FL1, Fenix ARB-L21-5500 battery)

Turbo: Output 5000 lumens, Distance 242 m, Intensity 14,641 cd, Impact Resistance 1 m, Submersible IP68 (short-burst mode; runtime not rated for sustained use)
High: Output 1500 lumens, Runtime 3h 40m, Distance 130 m, Intensity 4225 cd, Impact Resistance 1 m, Submersible IP68
Med: Output 350 lumens, Runtime 9h 40m, Distance 63 m, Intensity 992 cd, Impact Resistance 1 m, Submersible IP68
Low: Output 150 lumens, Runtime 26h 30m, Distance 41 m, Intensity 420 cd, Impact Resistance 1 m, Submersible IP68
Eco: Output 30 lumens, Runtime 89h 30m, Distance 18 m, Intensity 81 cd, Impact Resistance 1 m, Submersible IP68
Strobe: Output 2500 lumens, Impact Resistance 1 m, Submersible IP68

Specifications are Fenix lab testing results using one ARB-L21-5500 battery at 21±3°C and 50–80% humidity. Turbo mode delivers an ultra-high brightness burst for a short duration and cannot be sustained; its runtime is not listed.

Usage and Maintenance

Disassembling the sealed head can cause damage to the flashlight and will void the warranty.
Fenix recommends using an excellent quality battery.
If the flashlight will not be used for an extended period, remove the battery to avoid damage from electrolyte leakage.
Lock the flashlight or take out the battery to prevent accidental activation during storage or transportation.
Long-term use can result in O-ring wear; replace with an approved spare to maintain a proper water seal.
Periodic cleaning of the battery contacts improves performance; clean with a cotton swab soaked in rubbing alcohol if flickering occurs, or contact your authorized distributor.

What's Included

Fenix E40R flashlight, ARB-L21-5500 battery, lanyard, spare O-ring, USB Type-C charging cable, user manual, warranty card.

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