Description, Features & Specifications

Description

The ACW-GB139 Nozzle with Tool Adjust NPAS from Atlas Custom Works is a precision upgrade designed for gas blowback rifle users who need reliable control over power output. Machined from aluminum, this nozzle is built to withstand repeated cycling while maintaining consistent performance under demanding use. Finished in a clean silver color, it is engineered specifically for compatibility with the WA M4A1 GBB series and related platforms including INO, AGM, and PRIME systems that follow the Western Arms specification. As a replacement or upgrade component, this nozzle integrates seamlessly into compatible gas blowback rifles, making it a practical solution for players tuning their rifle for field limits, indoor play, or specific training requirements. Its durable construction and precise fit make it suitable for both maintenance and performance focused builds.

What sets the ACW-GB139 apart is its integrated NPAS design, which allows users to fine tune muzzle velocity and gas efficiency without swapping internal parts. Using the included adjustment tool, users can dial in power output to meet field regulations or optimize consistency for different environments. This level of control is especially valuable for gas blowback airsoft rifles, where temperature and gas pressure can impact performance. Designed with experienced users in mind, the nozzle supports controlled airflow and stable cycling when properly installed and adjusted. Atlas Custom Works is known for producing upgrade components that balance durability with performance, and this NPAS nozzle follows that approach. Ideal for serious airsoft players, technicians, and gas blowback enthusiasts, the ACW-GB139 helps improve adjustability, reliability, and long term usability of WA pattern M4 GBB rifles. Whether you are replacing a worn nozzle or upgrading for better velocity control, this component provides a clean, effective solution for gas blowback airsoft tuning while maintaining compatibility with proven Western Arms based platforms.

In the Box
1X GBB NPAS Set

Specifications:
Build: Aluminum
Compatibility: WA M4A1 GBB series
Color: Silver
Manufacturer: Atlas Custom Works

California Proposition 65 Warning: Cancer and Reproductive Harm - www.P65Warnings.ca.gov

Description

The ACW-GB139 Nozzle with Tool Adjust NPAS from Atlas Custom Works is a precision upgrade designed for gas blowback rifle users who need reliable control over power output. Machined from aluminum, this nozzle is built to withstand repeated cycling while maintaining consistent performance under demanding use. Finished in a clean silver color, it is engineered specifically for compatibility with the WA M4A1 GBB series and related platforms including INO, AGM, and PRIME systems that follow the Western Arms specification. As a replacement or upgrade component, this nozzle integrates seamlessly into compatible gas blowback rifles, making it a practical solution for players tuning their rifle for field limits, indoor play, or specific training requirements. Its durable construction and precise fit make it suitable for both maintenance and performance focused builds.

What sets the ACW-GB139 apart is its integrated NPAS design, which allows users to fine tune muzzle velocity and gas efficiency without swapping internal parts. Using the included adjustment tool, users can dial in power output to meet field regulations or optimize consistency for different environments. This level of control is especially valuable for gas blowback airsoft rifles, where temperature and gas pressure can impact performance. Designed with experienced users in mind, the nozzle supports controlled airflow and stable cycling when properly installed and adjusted. Atlas Custom Works is known for producing upgrade components that balance durability with performance, and this NPAS nozzle follows that approach. Ideal for serious airsoft players, technicians, and gas blowback enthusiasts, the ACW-GB139 helps improve adjustability, reliability, and long term usability of WA pattern M4 GBB rifles. Whether you are replacing a worn nozzle or upgrading for better velocity control, this component provides a clean, effective solution for gas blowback airsoft tuning while maintaining compatibility with proven Western Arms based platforms.

In the Box
1X GBB NPAS Set

Specifications:
Build: Aluminum
Compatibility: WA M4A1 GBB series
Color: Silver
Manufacturer: Atlas Custom Works

California Proposition 65 Warning: Cancer and Reproductive Harm - www.P65Warnings.ca.gov

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XTREME Superstore by Atlas Custom Works

ACW-GB139

Atlas Custom Works WA Nozzle w/ Adjustable NPAS Set

$75.00
$75.00
Shipping calculated at checkout.
Fits optimally as a replacement part or performance upgradeAllows adjustment of power output on compatible GBB riflesNozzle can ...  Read more
  • Fits optimally as a replacement part or performance upgrade
  • Allows adjustment of power output on compatible GBB rifles
  • Nozzle can be adjusted using the included tool
  • Designed for compatibility with the Western Arms M4 GBB series
  • Internal airsoft modifications require skill and proper technique
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