SA M4 CQB RL M-LOK Gen2 (SA-F04-RL FLEX™ HAL ETU™) – Half-Tan

Specna Arms M4 CQB RL M-LOK Gen2 (SA-F04-RL FLEX™ HAL ETU™) in black & tan finish is a high-performance airsoft rifle with 115 m/s power and upgraded internals. It features a HAL ETU™ processor unit with pre-cocking and trigger sensitivity adjustment, along with a nylon RL AR15 body and M-LOK handguard. The TDC hop-up chamber with Helium™ flat bucking ensures excellent accuracy.

Another product variants

  • Black
    On stock

177,20 € tax incl.

Availability: In Stock at store

4 Items  

SPARMS396-TAN

: Specna Arms

Accessories

  • 10,57 € In Stock

    : Wosport

    MAG022

    Ms2 MULTI-FUNCTION SLING tactical sling from WoSporT in black. For airsoft and real firearms, including duty use. 2-point sling with the option to switch to 1-point. MS2 sling replica in Magpul style. Heavy-duty steel carabiners with quick release and safety lock.

    10,57 €
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  • 7,61 € In Stock

    : IMAX

    IMAX04

    Digital Battery Capacity Checker by IMAX in black. Accurate status monitoring for Li-Pol, LiFe, Li-Ion, NiMH, and NiCd batteries. Supports 2–7 cells (Lithium) and 4–7 cells (NiCd/NiMH). Displays voltage, cell differences, and remaining capacity in percent Compact tester for airsoft and RC models.

    7,61 €
    On the way
  • 9,26 € In Stock

    : BLS

    1KG-H25

    BLS PRECISION Airsoft Pellets weighing 0.25 g in a pure white finish. 1 kg package (resealable bag, 4000 BBs). The most popular ammunition for all airsoft guns (rifles, sniper rifles, LMGs, SMGs, shotguns, and pistols). Suitable for AEG, HPA, gas guns, and spring-powered replicas. The world’s best-selling BBs. Hand-measured quality control. BLS –...

    9,26 €
    In Stock
  • 9,68 € In Stock

    : BLS

    1KG-H28

    BLS PRECISION Airsoft Pellets weighing 0.28 g in a pure white finish. 1 kg package (resealable bag, 3500 BBs). The most popular ammunition for all airsoft guns (rifles, sniper rifles, LMGs, SMGs, shotguns, and pistols). Suitable for AEG, HPA, gas guns, and spring-powered replicas. The world’s best-selling BBs. Hand-measured quality control. BLS –...

    9,68 €
    In Stock
  • 37,64 € In Stock

    : PTS

    PTS003

    EPM 150 BBs Mid-Cap Magazine for M4 / AR15 by PTS Syndicate in black. Compatible with all AEG M4 rifles using the TM standard. Full capacity indicator for quick status check. Transparent window with dummy rounds. Flawless BB feeding, even with heavy sniper ammo. Durable DuPont Zytel polymer body for maximum strength. Revised 2023 version.

    37,64 €
    In Stock
  • 14,80 € In Stock

    : BLS

    1KG-PLA25

    BLS BIO airsoft BBs weighing 0.25 g in white finish. 1kg package (resealable bag, 4000 BBs). The most popular BB ammo for all airsoft guns (rifles, snipers, LMGs, SMGs, shotguns and pistols). Biodegradable (BIO PLA). Suitable for AEG, HPA, gas guns and spring-powered replicas. The best-selling BBs in the world. BLS – Bestial Luxury Shots.

    14,80 €
    In Stock
  • 15,22 € In Stock

    : BLS

    1KG-PLA28

    BLS BIO airsoft BBs weighing 0.28 g in white finish. 1kg package (resealable bag, 3500 BBs). The most popular BB ammo for all airsoft guns (rifles, snipers, LMGs, SMGs, shotguns and pistols). Biodegradable (BIO PLA). Suitable for AEG, HPA, gas guns and spring-powered replicas. The best-selling BBs in the world. BLS – Bestial Luxury Shots.

    15,22 €
    In Stock
  • 10,15 € In Stock

    : Specna Arms

    SPARMS029-BK

    S-MAG Hi-Cap Magazine for AEG M4 / AR15 Rifles (MK18, HK416) by Specna Arms in black. 380 BBs capacity. Reliable winding, perfect feeding, less frequent reloading. Durable polymer body with texture for a secure grip. Slim profile suitable even for tight pouches. Best choice for Specna Arms PRIME™ rifles and other series.

    10,15 €
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  • 9,30 € In Stock

    : Specna Arms

    SPARMS030-BK

    S-MAG Mid-Cap Magazine for AEG M4 / AR15 Rifles (MK18, HK416) by Specna Arms in black. 125 BBs capacity. Reliable feeding even at high RoF and with heavier BBs. Durable and lightweight polymer body with textured surface for a secure grip. Slim profile suitable even for tight pouches. Best choice for Specna Arms PRIME™ rifles and other series.

    9,30 €
    In Stock
  • 69,78 € In Stock

    : Aim-O

    AIMO023

    69,78 €
    On the way
  • 93,04 € In Stock

    : FMA

    TB1075-BK

    AN/PEQ15 LA5-C Ultra High Power airsoft version by FMA in black color. LED flashlight with functional IR covers. More powerful green and IR laser for use with NVG. Compact size and durable nylon body. Mounts on RIS rail for weapons like M4, MK18, AK, CZ EVO, and others. PEQ box adds tactical versatility without adding weight. Powered by 2 CR123A...

    93,04 €
    In Stock
  • 16,49 € In Stock

    : TITAN

    TIT001

    TITAN Protective Fireproof Battery Bag in black. Designed to protect during charging and minimize the risk of damage in case of ignition. Ideal for storing all types of batteries (Li-Pol, Li-Ion, NiMh). Made from fire-resistant laminated fabric. Secure Velcro closure. Dimensions: 24.5 x 10.5 cm.

    16,49 €
    In Stock
  • 12,69 € In Stock

    : Wosport

    WOSP166-BK

    WoSporT quick-adjust 2-point sling FARAON in black finish is a universal weapon sling designed for fast handling. It allows an instant transition from secured carry to shooting position and features a rubberized pull tab for a firm grip. The design is based on proven Ferro Slingster-type slings with additional improvements for comfortable use.

    12,69 €
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  • 8,46 € In Stock

    : Delta Armory

    DA018-BK

    Delta Armory DMAG Mid-Cap Magazine for 120 BBs for AEG / HPA M4 (and similar models) in black. Fits most guns on the market (Specna Arms, CYMA, E&C, etc.) Thanks to the strong spring, it handles heavier ammo and higher rates of fire. It mimics the design of PMAG with a durable polymer body. Fits standard AR15 and 5.56 pouches.

    8,46 €
    In Stock
  • 63,01 € In Stock

    : Vector Optics

    SCRD-41

    MAVERICK 1x22 Gen3 Red Dot Sight by Vector Optics in black (S-MIL). The best-selling airsoft red dot sight. 3 MOA dot for fast aiming. 11 brightness levels of red illumination. Side-loading battery tray for replacement without losing zero. Rubber-armored body for scratch resistance. Optical center height 41 mm. Includes a killflash to prevent lens...

    63,01 €
    On the way
  • 33,41 € In Stock

    : TITAN

    TIT025

    TITAN 11.1V 1200 mAh Li-Po Battery with a discharge rate of 25C in Stick (buffer) configuration. Dimensions: 126 x 19 x 17 mm. Connector: T-Dean. Excellent performance, rate of fire, longer battery life and better trigger response. Ideal for AEG assault rifles, LMG, SMG / PDW and DMR weapons. Charge only with high-quality, powerful chargers. Don’t...

    33,41 €
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  • 28,33 € In Stock

    : TITAN

    TIT027

    TITAN 11.1V 1000 mAh Li-Po Battery with a discharge rate of 25C in Stick (buffer) configuration. Dimensions: 105 x 19 x 17 mm. Connector: T-Dean. Excellent performance, rate of fire, longer battery life and better trigger response. Ideal for AEG assault rifles, LMG, SMG / PDW and DMR weapons. Charge only with high-quality, powerful chargers. Don’t...

    28,33 €
    In Stock
  • 24,95 € In Stock

    : Specna Arms

    SPARMS266

    EASY LiPo Charger and 11.1V 1000mAh, 20C Battery Set by Specna Arms. Ideal for beginners and advanced users. Reliable and safe charger without unnecessary features. The battery is suitable for AEG AR15 rifles (M4, MK18), AR9 with wiring in the stock tube including small PDW stocks. LED light indicates charging (red) and fully charged (green). Battery...

    24,95 €
    In Stock
  • 168,74 € In Stock
    Free shipping

    : Specna Arms

    SPARMS274-BK

    Specna Arms EDGE™ set of Maverick-IV red dot sight and 3x magnifier in black. Accuracy and reliability in a value package. Quick attachment with QD mount on a RIS rail. Excellent combo offering the option for close-range (CQB) and medium-range shooting with a 3x flip-to-side magnifier. Suitable for AEG, GBB, and HPA guns. Magnifier is also suitable...

    168,74 €
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  • 52,86 € In Stock

    : Gens ACE

    GEA60WE1

    G-TECH iMars Mini Charger by Gens ACE in black. Set includes power adapter and USB-C cable. Up to 60 W charging power. Supports smart G-TECH batteries. Designed for Li-Po, Li-Ion, LiFe (2-4S) and NiMH batteries (2-12S). Suitable for FPV drones, airsoft, and RC models. Powered via USB-C (PD, QC, etc.). XT60 and T-Dean adapters included. 

    52,86 €
    In Stock
  • 21,15 € In Stock

    : Gens ACE

    GEA10003S25D

    LiPo Battery 11.1V - 1000 mAh (25C) by Gens ACE in Buffer stick configuration. Dimensions of 103 x 18 x 16 mm. T-Dean connector. High-performance 11.1V LiPo battery with 25C discharge rate. Increases rate of fire and improves motor response. Suitable for AEG rifles, machine guns, SMG/PDW, and DMR platforms. Use only with quality high-performance...

    21,15 €
    In Stock
  • 41,87 € In Stock

    : TITAN

    TIT032

    TITAN DIGITAL CHARGER V2 for Li-Po and Li-Ion batteries. V2 with USB-C charging and EU power adapter. 20% higher performance. Compact metal charger with a clearer digital display. Also works as a battery tester directly in the field. High safety thanks to a cell-by-cell balancing system. Supports 2S and 3S batteries (7.4V - 11.1V).

    41,87 €
    In Stock

Why Choose M4 CQB RL M-LOK FLEX™ Gen2 from Specna Arms?

Specna Arms M4 CQB RL M-LOK Gen2 (SA-F04-RL FLEX™ HAL ETU™) is built on a lightweight yet durable FLEX™ RL AR15 nylon body reinforced with glass fiber, offering a realistic matte finish and excellent resistance to wear, outperforming cheaper alloy bodies. This is the RL SAAS model (Specna Arms Accessory System), featuring a more aggressive design compared to standard AR15 receivers. The outer barrel with a 14 mm CCW thread and steel components such as pins, screws, and the ejection port provide strength where it matters. The result is a lightweight yet robust assault rifle platform, ideal for CQB environments and dynamic gameplay. The AR15 (M4) platform ensures intuitive controls. It features an ambidextrous charging handle, clear fire selector, and easy hop-up adjustment through the ejection port. The M-LOK handguard allows mounting accessories such as a foregrip, tactical flashlight, or PEQ box. The Light Ops stock with rubberized cheek rest and QD sling points keeps the setup lightweight. The battery is stored in the buffer tube, requiring a buffer stick battery. Overall, this rifle combines low weight, modern construction, and high-quality Gen2 internals. The FLEX™ Gen2 series stands out with internals such as the Æther™ gearbox, HAL ETU™, metal nozzle, TDC hop-up chamber with Helium™ flat bucking, and a 6.03 mm precision inner barrel.

Key Features of Specna Arms M4 CQB RL M-LOK FLEX™ Gen2

HAL ETU™ Processor Unit

Advanced features such as binary trigger, pre-cocking, trigger sensitivity adjustment, and protection for Li-Pol batteries.

Lightweight FLEX™ Construction

Glass fiber reinforced nylon body for low weight and high durability.

6.03 mm Barrel, TDC Hop-up & Helium™ Bucking

Improved accuracy and consistent trajectory thanks to the TDC hop-up system.

ESA™ QSC System & Æther™ Gearbox

Quick spring change ESA™ without disassembly. Reinforced Æther™ gearbox with 8 mm bearings.

M-LOK Handguard

Easy mounting of accessories like M-LOK grips, rails, flashlights, or PEQ box.

HAL ETU™ Programming

Overview of HAL ETU™ functions and setup.

Technical Specifications

  • Platform: M4 / AR15
  • Series: FLEX™ Gen2
  • Length: 670-750 mm
  • Weight: 2125 g
  • Power Source: AEG
  • Unit: HAL ETU™
  • Gearbox: Æther™ V2 QSC
  • Quick Spring Change: Yes (ESA™)
  • Hop-up: TDC
  • Inner Barrel: 6.03 mm
  • Velocity: 115 m/s
  • Bearings: 8 mm
  • Connector: T-Dean
  • Body Material: Fiber-reinforced nylon
  • Handguard: M-LOK
  • Thread: 14 mm CCW

Package Contents

  • Specna Arms M4 CQB RL M-LOK FLEX™ Gen2
  • Hi-cap magazine (300 BBs)
  • Flip-up sights
  • M90 spring
  • Specna Arms stickers
  • User manual

Important Notice Before First Use

To start using the rifle, it is necessary to activate the HAL ETU unit by following this exact procedure, otherwise the rifle will not respond to the connected battery:

  1. Set the fire selector to Safe
  2. Connect the battery and wait 3 seconds until you hear a beep
  3. Pull and hold the trigger for 5 seconds until you hear another beep
  4. The rifle is now ready to use
VariantsFLEX™ Gen2
ColorHalf - Tan
Muzzle velocity (m/s)115 (m/s)
Recommended weight of ammunition0,25g - 0,28g
Thread (mm)14- (mm)
Outer length MINIMAL (mm)670 (mm)
Outer length MAXIMAL (mm)750 (mm)
Inner barrel length (mm)229 (mm)
Weight (g)2130 (g)
Body/receiver materialABS / Plastic
Mounting SystemM-LOK
Gearbox versionV2 - ESA™
Amount of piston teeth14
Bearings (mm)8 (mm)
Bearings (material)Metal
Piston headPlastic
NozzleMetal
Spring guidePlastic
Hop-Up chamber materialPlastic
Battery typeBuffer stick
Connector typeT-Dean
Magazine materialPlastic
High-cap / Mid-capHigh-cap
Magazine capacity300
Processor unitYES
BlowbackNO
Battery includedNO
Battery ChargerNO
Weapon accessoriesYes