GTP9/SMC9 to M4 HPA Adapter - AIRTACUK
GTP9/SMC9 to M4 HPA Adapter - AIRTACUK
GTP9/SMC9 to M4 HPA Adapter - AIRTACUK


GTP9/SMC9 to M4 HPA Adapter

Sale price£69.99
Pickup available at Open Mon-Thu 4-6pm Usually ready in 2-4 days

GTP9/SMC9 to M4 HPA Adapter

Open Mon-Thu 4-6pm

Pickup available, usually ready in 2-4 days

Unit 27/28
Ballymena Business Centre
Galgorm BT42 1FL
United Kingdom

In stock


  1. Compatible with short GTP/SMC9 gas magazine

  2. CNC Mag Release and Feed Tube

  3. Includes single stack adapter

  4. BB retention mechanism to reduce BB loss during magazine changes

  5. US HPA FITTING as standard

We’ve taken feedback on thousands of M4 HPA adapters sold throughout 2022, to build what we believe to be the perfect HPA adapter. A CNC feed tube and recessed CNC mag release provide lifelong longevity, a flared magwell enables speedy mag changes, and an adjustable shim gives excellent magazine compatibility and fitment (though you won’t need it for most magazines!).

Our whole team worked their magic in creating a beautiful aesthetic that suits the pistol, while still allowing the use of flared mag-wells and keeping bulk to a minimum.

It doesn’t end there, we offer excellent product support, lifetime warranty, and include spare parts should you or your team ever need them!


Installation is dead simple, you’ll need a quick grip vice such as this, a pin punch (2mm), basic screwdriver set and a hammer or mallet.

1) Punch out the bottom pins on the sides of the gas magazine to remove the gas block.

2) Punch out the small pin that retains the follower at the bottom of the gas magazine

3) Insert the single stack adapter into the gas magazine

4) Fit the gasket to the Airtac HPA adapter (at this stage you can apply some silicone oil to the gasket to aid insertion )

5) Place the HPA Adapter into the magazine, and into the clamp. Tighten the clamp until the pin holes line up, and gently hammer them in

8) Go have fun!

M4 Adapter Info

  • Compatible with most airsoft M4 magazines. We recommend EPM1/EPM1s magazines for high ROF setups, as they have the strongest springs
  • 2-3 BBs are dropped when changing mag
  • Image below shows fileable/replaceable rear shim