Phase 5 Weapon Systems LOPROGAS Lo-Pro Gas Block Mag Phosphate 4140 Chromoly Steel 0.95"

The Phase 5 Weapon Systems LOPROGAS Lo-Pro Gas Block is a low-profile alternative to traditional front sight gas blocks, engineered for AR builders who want a clean, minimal upper receiver profile without sacrificing function. Built from 4140 chromoly steel with a mag phosphate finish, this gas block is designed to mount directly to a 0.750" barrel diameter using a clamp-style interface secured by two clamping screws. It's the kind of purposeful, no-frills component that works just as hard as the rest of your rifle.

The lo-pro design means you can run a rifle-length forearm on a carbine-length barrel without the bulk and sight radius of a traditional front sight post. At just 1.8 oz, it adds negligible weight while giving you a streamlined platform for optics or a clean top rail. The mag phosphate finish provides solid corrosion resistance and the classic matte look you'd expect from a duty-oriented AR part. This is the gas block for shooters who care more about ergonomics and modularity than extra features.

Installation is straightforward: the two clamping screws handle all the securing work. Note that the gas tube roll pin is not included—that comes with Phase 5's gas tubes separately. Whether you're building an SBR, a precision rifle, or just want a slimmer upper receiver without visual clutter, the LOPROGAS delivers function and form in a single, lightweight package.

Key Features

• Low-profile design for streamlined upper receiver build
• 4140 chromoly steel construction with mag phosphate finish
• Clamp-style mounting with two screws for secure attachment
• Compatible with 0.750" barrel diameter
• Weighs only 1.8 oz
• Allows rifle-length forearm compatibility on carbine-length barrels

Specifications

Frequently Asked Questions

Will this lo-pro gas block work with my 0.750" barrel?

Yes. The LOPROGAS is designed to clamp onto 0.750" diameter barrels. Verify your barrel OD before ordering to ensure a proper fit.

What's included in the box?

You get the gas block itself and two clamping screws for installation. The gas tube roll pin is sold separately and comes with Phase 5 gas tubes.

Can I use this on a rifle-length or carbine-length build?

The LOPROGAS is designed to allow a rifle-length forearm to mount on a carbine-length barrel, giving you flexibility in your build configuration while keeping a low-profile footprint.

How much does this weigh?

The LOPROGAS weighs 1.8 oz, making it a minimal addition to your upper receiver without adding unnecessary heft.