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PolarStar JACK + Silent Industries ALPHA · Alignment Kit V2.1 · M4 AEG HPA / ICS
PolarStar JACK + Silent Industries ALPHA · Alignment Kit V2.1 · M4 AEG HPA / ICS

PolarStar JACK + Silent Industries ALPHA alignment kit for M4 AEG (v2.1)

23,00 €
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Version 2.1 of the hop-up alignment system, designed for M4 AEG HPA replicas with V2 or ICS split gearboxes using:

  • PolarStar JACK Engine (single-solenoid HPA engine, simple, efficient, and widely used).
  • Silent Industries ALPHA M4/16 AEG/HPA Chamber (CNC hop-up chamber with TRUE-TDC and precise bucking control).

This version of ALPHA is from before 2026; the body is rounded.

This kit ensures solid and precise alignment between the JACK nozzle and the ALPHA chamber, preventing misalignment, double feeds, and shot inconsistency—something critical in high-ROF HPA builds.

Compatibility

Component Compatibility
HPA Engine PolarStar JACK
Hop-up Chamber Silent Industries ALPHA M4/16 AEG/HPA
Base Replica M4 AEG
Gearbox V2 / ICS SPLIT

What the kit includes

  • Rear clip for mounting via rear pin or fixed stock.
  • Base with housing for M3 inserts (brass optional).
  • Side clip for routing the HPA line.
  • Top cap for front locking of the ALPHA chamber.
  • Rear plate with mounting point for an M5 screw, providing extra rigidity to the assembly.

Installation and adjustment

  1. Printing and preparation

    • Print the parts with 65–80% infill.
    • Lightly sand internal surfaces for a smooth fit.
    • You can apply dry lubricant or wax to ease assembly and maintenance.

  2. Installation in the replica

    • Insert the base into the lower and install the M3 inserts.
    • Place the rear clip aligned with the rear pin or the stock mounting point.
    • Install the ALPHA chamber with the inner barrel; the top cap locks and centers the assembly.
    • Route the JACK HPA line through the side clip to prevent bending.

  3. Final fixing and testing

    • Secure the rear plate with an M5 screw and washer for maximum rigidity.
    • Check that the PolarStar JACK nozzle enters the ALPHA chamber centered and that feeding is clean during dry and live firing tests.

Required components (not included)

  • 4× M3 inserts × 4.2 mm
  • 4× M3 × 8 SHCS screws

Recommended lower

Using the ICS metal lower is recommended for very demanding builds.
If you prefer to print the lower receiver, this kit is compatible with:

  • Gearbox v2 Lower "Universal lower part" Version 3
  • Gearbox v2 Lower "Universal lower part" Version 4.2
  • Gearbox v2 Lower "Universal lower part" Version 4.3 MTW

You can find them in the products section by clicking Here

3D printing parameters

  • Approximate print time: ~1 h 30 min
  • Recommended material: PLA+
  • Layer height: 0.10 mm – 0.15 mm

Manuals

Assembly and adjustment manuals are available in the Manuals section of the website or on the project's Discord server.

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Frequently asked questions

What material and dimensions apply to PolarStar JACK + Silent Industries ALPHA alignment kit for M4 AEG (v2.1)?

The public product data does not declare a material or finished dimensions for this design. Check the images, downloadable files, and the exact manufacturing or printing setup before producing it.

What is PolarStar JACK + Silent Industries ALPHA alignment kit for M4 AEG (v2.1) compatible with?

The published tags and categories identify this design with m4, polarstar, jack, polarstar jack, silent industries alpha, alpha chamber. Confirm the exact platform, revision, and mounting points before ordering.

How do I install or prepare PolarStar JACK + Silent Industries ALPHA alignment kit for M4 AEG (v2.1)?

Read the installation notes in the product description, inspect the supplied files and images, and test alignment before final fastening. The required tools, fasteners, printing parameters, or post-processing depend on the specific build.

What are the real-world uses for PolarStar JACK + Silent Industries ALPHA alignment kit for M4 AEG (v2.1)?

This design is intended for projects related to m4, polarstar, jack, polarstar jack, silent industries alpha, alpha chamber. It is useful for a compatible repair, conversion, prototype, replacement, or custom build when the published fitment and project requirements match.