SA M4 Carbine M-LOK (SA-P20 PRIME™ ASTER II ETU BLDC™) - Green

Specna Arms M4 Carbine M-LOK (SA-P20 PRIME™ ASTER II ETU BLDC™)

Looking for a tuned-up airsoft M4 rifle with a durable metal body? Do you want your rifle to have top-tier internals and the Gate ASTER II Bluetooth® electronic control unit? Want to easily configure the rifle’s functions via a mobile app? Then this PRIME™ series M4 rifle is the right choice for you. PRIME™ is the top tier. It represents the best, most refined, most tuned and most reliable products Specna Arms offers. In short, Specna took the perfectly fitted body from the Edge/Edge 2.0 series with a Nano Coating finish for enhanced scratch resistance, and filled it with high-end upgrade parts.
The upgrade began with the motor. A brushless motor installed inside a new QD pistol grip for quick motor access. Inside the rifle, you will also find a completely redesigned ÆTHER gearbox capable of handling M140 AEG springs. It houses the ASTER II ETU Bluetooth control unit with a CNC GATE x SA SOLAR™ trigger, CNC 16:1 gears, CNC cylinder and piston head with CNC nozzle, 8mm ball bearings on the spur and bevel gear, and a bush bearing on the sector gear. Precision is ensured by a 6.02 mm inner barrel combined with a Helium Flat-Hop bucking inside the redesigned MAGNUS™ TDC hop-up chamber.
The package includes 3 different AEG springs, so you can head into a CQB arena with an M90 spring. Thanks to the ESA2 quick spring change system, you can install an M115 spring for field limits within minutes. Or you can put in the strongest included spring, M135, and turn your rifle into a precise DMR with excellent range. If you want a universal airsoft rifle built from the best components that requires no further investment, then the PRIME™ series is the right choice. From fast CQB gameplay to a precise DMR rifle firing single shots, this is the magic of PRIME™. The package also includes 2 S-MAG mid-cap magazines (125 BBs) and a speedloader for easy filling.

Specna Arms M4 Carbine M-LOK (SA-P20)

Gate ASTER II Bluetooth® Control Unit

It ensures safe switching to protect internal components, improves trigger response, extends battery life, increases RoF and allows safe use of 7.4V and 11.1V Li-Po batteries. The battery connector is T-Dean with wiring routed into the buffer tube.

ASTER II features:

• Trigger sensitivity adjustment – 5 optical sensors allow extremely precise and sensitive trigger settings
• Burst mode adjustment – 2 to 10 rounds, with only 4 ms between shots
• Selectable fire selector modes – SAFE – SEMI/BURST – BURST/AUTO and more
• Pre-cocking – pre-loads the piston immediately after the shot for a sharper trigger response in SEMI
• Rate-of-fire control (RoF limit)
• DMR mode – adjustable delay between semi-auto shots
• Smart trigger – ideal when combined with RoF reduction; first shot is full-speed, remaining shots follow selected RoF limits
• Battery protection & low-voltage warning – ASTER detects battery cell count and disables firing when voltage drops, accompanied by motor vibration
• Smart fuse – protects the motor and electronics from overheating or overload
• Active brake – reduces motor wear through controlled braking instead of instant stop

Gate Control Station Bluetooth App

Using the app for Android, iOS or Windows/Mac you can easily configure the control unit. All functions are displayed clearly on your phone without a programming card or trigger clicks. The app also allows firmware updates to keep your unit up to date.

PRIME™ gearbox M4

Technical Specifications

• Power system: AEG
• Material: Metal, polymer
• Rifle length: 750–830 mm
• Weight: 2640 g
• Muzzle velocity: 130 m/s (1.7 J)
• Inner barrel length: 315 mm
• Inner barrel diameter: 6.02 mm
• Hop-up: Adjustable (TDC)
• Fire modes: Semi, Full Auto, Binary, Pre-Cocking and more
• Thread: 14mm CCW (counter-clockwise)
• Handguard: M-LOK
• Compatible battery: 11.1V Li-Po (not included)
• Connector: T-Dean
• Compatible battery type: Crane (Buffer stick, Nunchuk)
• Magazine capacity: 125 BBs (Mid-Cap)
• Motor type: Brushless (Specna Arms Dark Matter 27–35k)

Package Contents

• Specna Arms PRIME™ M4 AEG rifle
• 2× S-MAG mid-cap magazines (125 BBs)
• Small Tamiya adapter
• Speedloader
• Iron sights
• M90 spring (CQB)
• M115 spring (standard field)
• M135 spring (DMR setup)
• Specna Arms stickers
• User manual

Warnings

• Springs from some manufacturers are significantly overpowered (e.g., an M130 may behave like M140–150), possibly exceeding gearbox durability. We recommend using only the included Specna Arms springs. For other brands, M120-class springs are recommended to avoid damage.
• If installing a spring with progressive (irregular) winding, ensure the tighter coil end is placed on the spring guide facing outward.
• Never store the rifle with the battery connected.
• Never store the rifle with pre-cocking active. Always release the piston before storage to avoid spring wear.

Gate Control Station (GCS) App Download

• Android
• iOS
• Windows/Mac

Pairing the App

To pair the GCS app with the ASTER II unit, you must enter its code located on the wiring label. Do not remove this label, or store it safely. Without the code, pairing with the app is not possible.