SA M4 Special Operation HAL ETU™ (SA-C05 CORE™) - Black/Tan

Assault Rifle M4

M4 is a compact automatic rifle, developed in the United States based on the popular M16 assault rifle. It was designed with the need for a lighter and shorter version of the M16, suitable for use in close quarters and urban combat.
In the 1960s, the M16, developed by Armalite and adopted by the U.S. military, served as the basis for the M4. In the 1980s, the first M4 prototypes appeared, featuring a shorter barrel and telescopic stock, improving maneuverability in confined spaces.
In the 1990s, the M4 was officially adopted by the U.S. armed forces as the standard carbine, replacing older models such as the M3 and M9. The rifle is capable of both semi-automatic and burst fire, making it a versatile weapon.
The M4 quickly became a favorite among soldiers due to its light weight, compactness, and reliability. It was widely used in conflicts such as the Iraq and Afghanistan wars and has become an iconic weapon of the modern U.S. armed forces.
Besides the standard model, there are many M4 variants equipped with various accessories and upgrades to meet the specific needs of military units.
The airsoft AEG M4 assault rifle in the basic CORE™ series by Specna Arms emphasizes lightweight nylon body construction while also focusing on top-notch craftsmanship and fit. The body is reinforced with glass fibers and is more durable than the typical zinc alloy of cheap metal bodies, which will be appreciated not only by beginners but also by advanced players who prefer fast-paced action in the style of speedsoft, where every gram counts. This type of body can also be found on weapons like the CZ Scorpion Evo or the MP7.

What does the Specna Arms M4 Special Operation HAL ETU™ (SA-C05 CORE™) offer?

Internal Parts

The M4 Special Operation HAL ETU™ (SA-C05 CORE™) replica is equipped with the HAL ETU™ electronic processor unit, which takes the weapon's performance to a whole new level. This upgrade elevates Specna Arms from the mid-tier to the elite league of prestigious brands offering the latest technological features in the basic variants of their weapons.
The name HAL is derived from the principle of the Hall effect, which allows the unit to detect trigger sensitivity.
Already in its base form, the M4 is equipped with a precise 6.03 mm barrel, which enhances accuracy, and an adjustable Hop-up chamber with a quality rubber.
Additionally, a feature that is becoming increasingly common nowadays is the QSC system ESA (quick spring change), which allows you to install a stronger or weaker spring according to your preference. The spring can be changed without removing the gearbox from the weapon's body, everything is done easily through the buffer tube.
The gearbox is also reinforced and is capable of working with springs up to M120 (as stated by the manufacturer Specna Arms).

The HAL ETU™ unit offers the following features:

• Trigger detection based on magnetic sensors and the Hall effect
• Active brake
• Binary trigger (shot on pull and shot on release)
• Adjustable trigger sensitivity (5 levels from 20 to 100%)
• Adjustable pre-cocking (6 levels)
• Programmable SEMI firing modes (semi, binary, AUG, sniper with delay)
• Programmable AUTO firing modes (auto, semi, 3-round burst, 5-round burst)
• Easy programming via the trigger
• Low battery warning
• Compatible with brushless motors (such as the Specna Arms Dark Matter or Warhead)

External Parts

The Specna Arms M4 Special Operation HAL ETU™ (SA-C05 CORE™) replica stands out for its high-quality nylon body with a matte finish, giving it a very realistic appearance. Reinforced with glass fibers, it is both highly durable and lightweight.
The outer barrel is made of metal, and the screws, ejection port, and pins are even made of steel. The ergonomic design of AR15 rifles and the modern construction ensure comfortable handling and easy operation, this rifle simply feels right!
The CNC metal RIS handguard allows for the attachment of various accessories such as grips, AN/PEQ box, flashlight, etc. With an adjustable Crane stock, this replica is ready for various game scenarios and allows the insertion of batteries (type Buffer Stick, Nunchuck, or Crane).
Overall, this rifle combines excellent performance with an attractive price for maximum player satisfaction.

Important Notice for Weapon Activation

In order to fire the weapon, it is necessary to activate the HAL ETU unit and follow this exact procedure. Otherwise, the weapon will not respond to the connected battery:

1. Switch the fire selector to the Safe position.
2. Connect the battery and wait for 3 seconds until you hear a beep.
3. Press and hold the trigger for 5 seconds until you hear another beep.
4. The weapon is now ready to use.

Key Features

• High-quality nylon body reinforced with polymer fibers
• HAL ETU™ V2 processor unit
• Crane-type stock for multi-piece batteries
• V2 gearbox with QD ESA quick spring change system
• Reinforced polymer piston with all-steel teeth
• Polymer nozzle
• Polymer cylinder head with sealing and metal nozzle tip
• Polymer piston head with sealing
• 8mm metal slide bearings
• Gear set with a standard 18:1 ratio
• Polymer rotary hop-up chamber
• Precise barrel with a diameter of 6.03 mm

Package Includes:

• Specna Arms AEG rifle
• Hi-Cap magazine S-MAG for 380 BBs
• Folding sights
• Spare weaker spring (M90) for CQB
• Specna Arms promotional stickers
• User manual

We can re-solder the connector to another type upon request. Just write the request in the order note.