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SIG M17/M18 M4 Adapter

In Development

Looking for an adapter for your GBB that we don’t offer yet? Submit a request here.

We’ve redesigned our Adapter into a full one-piece design. This allows us to make the adapter as compact and ergonomic as possible.

We don’t want our customers to make a mistake during installation, so we do it for you. Because of this, we offer a full 30-day warranty for the entire adapter.
We also offer a lifetime RMA process, you can send your adapter back for repair or replacement anytime (fees apply).


– Use AEG M4 magazines in your SIG M17/M18.
– HPA powered, we suggest 100-125 PSI.
– Enlarged mag release for faster reloads and protection.
– BB retention system to prevent wasting ammo.
– CNC adjustable feed nozzle. Never run into incompatible magazines again.
– HPA line. We’ve switched to an HPA line instead of a built-in tap. This creates less mass around your wrist to allow more movement.

What’s included:

– The full nine yards; Our adapters come fully assembled, no need to sacrifice an existing magazine for the feed lips or outlet valve.
– HPA Foster Fitting (US Spec)

Compatibility: SIG M17/M18.

SKU: sigm17m18-m4 Categories: ,