MT21A - Flashlight Nitecore - Free user manual and instructions

Product Type	Flashlight
Brand	Nitecore
Model	MT21A
LED Type	CREE XP-L HD V6
Max Output	1000 lumens
Beam Distance	250 meters
Peak Beam Intensity	15600 cd
Modes	Turbo, High, Mid, Low, Strobe, SOS, Beacon
Runtime (Turbo)	1 hour 15 minutes
Runtime (Low)	100 hours
Power Source	1x 18650 Li-ion or 2x CR123A
Dimensions	156 mm x 35 mm (head) x 25 mm (body)
Weight	120 g (without battery)
Impact Resistance	1.5 meters
Waterproof Rating	IPX-8 (submersible up to 2 meters)
Lens	Optical mineral glass with anti-reflective coating
Reflector	Aluminum texture reflector
Switch Type	Rear tactical switch with momentary-on
Body Material	Aerospace-grade aluminum alloy
Finish	HA III military-grade hard anodizing
Maintenance	Clean contacts with alcohol; lubricate O-rings with silicone grease
Safety	Do not shine directly into eyes; avoid exposure to extreme heat
Spare Parts	Tail switch, lens, O-rings available
Warranty	2 years limited warranty

Frequently Asked Questions - MT21A Nitecore

What battery types does the Nitecore MT21A use?

The MT21A uses either one 18650 Li-ion battery or two CR123A lithium batteries. It is compatible with rechargeable 18650 cells (protected or unprotected).

How do I change the battery in the MT21A?

Unscrew the tail cap, insert the battery with the positive (+) end facing the head, then reattach the tail cap securely. Ensure the battery contacts are clean.

What is the maximum output of the MT21A?

The maximum output is 1000 lumens on Turbo mode, with a beam distance of up to 250 meters.

Is the MT21A waterproof?

Yes, it has an IPX-8 rating, meaning it can be submerged up to 2 meters underwater for 30 minutes.

How do I switch between brightness modes?

Press the tail switch lightly for momentary-on; click fully for constant on. Cycle through modes by half-pressing the switch repeatedly.

Can I use rechargeable batteries in the MT21A?

Yes, the flashlight supports rechargeable IMR 18650 batteries with built-in protection. Ensure they are of good quality and voltage is within 3.0-4.2V.

What is the runtime on low mode?

On Low mode (15 lumens), the runtime is approximately 100 hours, making it ideal for long-duration tasks.

How do I clean and maintain the MT21A?

Clean the threads and contacts with a cotton swab and isopropyl alcohol. Lubricate the O-rings with silicone grease. Replace O-rings if damaged.

What is the warranty period for the MT21A?

Nitecore provides a 2-year limited warranty against defects in materials and workmanship. Extended warranty may apply for registered products.

Can I replace the tail switch myself?

Yes, the tail switch is user-replaceable. Unscrew the tail cap, remove the switch assembly, and install a new one (compatible with Nitecore parts).

USER MANUAL MT21A Nitecore

• LED Premium CREE XP-E2 R2 LED
• Maximum output of up to 260 lumens
- Integrated “Precision Digital Optics Technology” provides exceptional throw capability in its class.
- Boasts a peak beam intensity of 10,000cd and a throw distance of up to 200 meters
• Maximum runtime of up to 55 hours
- Two rapid switching modes suit various user requirements.
- User-defined mode allows for customized brightness levels and a multitude of functions
• Intelligent memory functions
- Reverse polarity protection
- Toughened ultra-clear mineral glass with anti-reflective coating
- Purpose designed reflector ensures a smooth and powerful beam
• Aero grade aluminum alloy
• HA III Military grade hard anodized
- Purpose-made rhombic knurling for better grip
- IPX-8 standard waterproof (submersible to two meters)

Dimensions

Length: 155mm (6.1")

Head Diameter: 25.4mm (1")

Tail Diameter: 21.5mm (0.85")

Weight: 68grams (2.4oz)(without battery)

Accessories

Lanyard, spare plastic cap, and spare O-ring

Battery Options

	TYPE	Nominal voltage	Compatible
Primary AA battery	AA 1.5V		Y (Recommended)
Rechargeable AA battery	AA 1.2V		Y (Recommended)
Primary AA Lithium battery	L91 1.5V		Y (Recommended)
Primary FeLiPO4 battery	14500 3.2V		N (Banned)
Rechargeable Li-ion battery	14500 3.7V		N (Banned)

Brightness & Runtime

FL1 STANDARD TURBO HIGH MID LOW
	260 LUMENS	130 LUMENS	60 LUMENS	15 LUMENS
	2h	5h	12h	55h
	200m (Beam Distance)
	10000cd (Peak Beam Intensity)
	1.5m (Impact Resistant)
	IPX-8, 2m (Waterproof AND Submersible)

NOTICE

Stated data has been measured according to the international

flashlight testing standards ANSI/NEMA FL1 using two high quality AA Ni-Mh

rechargeable batteries (1.2V, 2400mAh) under laboratory conditions. The data may vary due to individual usage

habits and environmental conditions.

Operation instructions

Battery Installation

1. Unscrew the tail cap in a counter-clockwise direction.
2. Insert two AA batteries with the positive pole pointing forward (toward the light head).

WARNING

1. Ensure batteries are inserted with the positive (+) end pointing to the head. The MT21A will not operate with incorrectly inserted batteries.
2. Please do NOT light directly to the eyes, which will hurt the eyes.

Switching ON/OFF

Switch ON: Press the button on the tailcap until a "click" is heard.

Switch OFF: Press the button at the tailcap a second time until a "click" is heard.

Mode Switching

The Nitecore MT21A has two modes: Turbo and user-defined. These two modes can be changed by simply tightening and loosening the flashlight head. Turbo provides 100% output while user-defined mode contains five selectable sub-modes.

Turbo Mode

Turbo mode is accessed when the MT21A flashlight is switched ON and the head lightly tightened. While in this mode, momentary illumination can be achieved by switching off the flashlight and then half pressing and holding the switch. Momentary illumination can be used as a flashing signal indicator or apply to various tactical applications.

Note: After three minutes' using of turbo mode, the flashlight will lower its output automatically for preventing overheating, and efficiently ensure the battery runtime.

User-Defined Mode

User-defined mode is accessed by slightly loosening the flashlight head. In this mode, lightly and rapidly pressing the switch will cycle through brightness and other functions in the following order: "High-Mid-Low- SOS-Strobe". Pressing the switch all the way down will save and memorize a desired setting.

Tips: Make NITECORE MT21A your perfect multi-task flashlight.

NITECORE MT21A flashlights essentially have two modes: Turbo mode (100% output) and custom mode. Turbo mode is accessed by tightening the flashlight head while any of one of the four customizable modes (strobe, low, medium and high) are selected by loosening the head and rapidly pressing the on/off switch to cycle through the modes. A given mode can be saved by simply turn off the light while in that mode. Real-world examples include: When used as a flashlight around the home, the head can be loosened and low level selected in custom mode, providing long runtimes at a lower light intensity. The same flashlight could then be taken out and used as a law-enforcement duty light, with user-defined mode set in strobe, making it easy to alternate between turbo mode and strobe with a simple twist of the flashlight head.

Maintenance

Every 6 months, threads should be wiped with a clean cloth followed by a thin coating of silicon-based lubricant.

Warranty Service

All NITECORE® products are warranted for quality. Any defective / malfunctioning NITECORE® product can be repaired free of charge for a period of 60 months (5 years) from the date of purchase. Beyond 60 months (5 years), a limited warranty applies, covering the cost of labor and maintenance, but not the cost of accessories or replacement parts.

The warranty is nullified in all of the following situations:

1. The product(s) is/are broken down, reconstructed and/or modified by unauthorized parties.
2. The product(s) is/are damaged through improper use.
3. The product(s) is/are damaged by leakage of batteries.

For the latest information on NITECORE® products and services, please contact a local NITECORE® distributor or send an email to [e-mail]

※All images, text and statements specified herein this user manual are for reference purpose only. Should any discrepancy occurs between this manual and information specified on www.nitecore.com, information on our official website shall prevail. Sysmax Industry Co., Ltd. reserves the rights to interpret and amend the content of this document at any time without prior notice.

SYSMAX Ind.

SYSMAX Industry Co., Ltd.

TEL: [phone]
FAX: [phone]
E-mail: [e-mail]
Web: www.nitecore.com
Address: Rm1407-08, Glorious Tower, 850 East Dongfeng Road, Guangzhou, China 510600