Griffin Armament 3-Lug 9mm Luger M13.5x1 LH TPI 17-4 Stainless Steel Black Melonite QPQ Adapter

The Griffin Armament 3-Lug 9mm Luger adapter is a HK-pattern muzzle device attachment built for shooters who want reliable, standardized suppressor mounting on their 9mm pistols and submachine guns. This M13.5x1 left-hand threaded adapter lets you connect any third-party 3-lug silencer that follows the HK standard, or pair it directly with Griffin's own 3-lug interface assemblies—giving you flexibility and cross-compatibility without being locked into a single brand ecosystem.

Built from 17-4 stainless steel and finished with Melonite QPQ treatment, this adapter is engineered to handle the rigors of training, duty use, and frequent suppressor attachment and removal. The QPQ process—a salt-bath nitriding technique—hardens the surface while preserving corrosion resistance, so your adapter stays reliable whether you're shooting suppressed indoors, in damp conditions, or after extended storage. The stainless core means no rust issues even if the finish gets dinged up on the job.

Whether you're running a 9mm carbine, MP5-pattern gun, or any other platform with M13.5x1 LH threading, this straightforward, no-fuss adapter bridges your barrel to the suppressor market's most widely adopted standard. It's the kind of part that disappears into your setup—until you realize how often you appreciate being able to use any compatible can without hunting for proprietary adapters.

Key Features

• HK-pattern 3-lug design: compatible with any standard 3-lug suppressor on the market
• Works with Griffin Armament 3-lug interface assemblies for integrated setups
• 17-4 stainless steel body: corrosion-resistant and durable
• Melonite QPQ surface treatment: hardened finish that resists wear and corrosion
• M13.5x1 left-hand thread: matches common 9mm Luger barrels

Specifications

Frequently Asked Questions

Will this adapter work with any 3-lug suppressor?

Yes. This is a HK-pattern 3-lug adapter, which is the industry standard. It will mount any third-party suppressor designed to that specification. It also works with Griffin Armament's own 3-lug interface assemblies if you want a fully integrated setup.

What does the Melonite QPQ finish do?

Melonite QPQ is a salt-bath nitriding process that hardens the steel surface to improve wear resistance and corrosion protection. It keeps the adapter functioning smoothly through repeated attachments and detachments, and protects against rust in storage or damp conditions.

Does my 9mm barrel have M13.5x1 LH threading?

M13.5x1 left-hand is a common 9mm thread pattern, but not universal. Check your barrel specifications before ordering. If your gun uses a different thread pitch or a right-hand thread, this adapter will not fit.

What's included with the adapter?

The order includes the adapter itself. You'll need a compatible suppressor with a 3-lug interface to complete the mounting setup.