NPAS
NPAS for Adjustable FPS and Controlled Gas Output
An NPAS (Negative Pressure Adjustment System) allows you to manually adjust the gas output of your gas blowback replica. This system is mounted in or on the nozzle and regulates how much gas is released per shot, allowing you to accurately adjust the FPS.
Within this category, you will find NPAS systems from Ra-Tech, a specialist in performance solutions for GBB platforms. This subcategory falls under GBB Parts and focuses on adjusting and fine-tuning gas blowback replicas.
What exactly does an NPAS do?
An NPAS replaces or modifies the standard nozzle valve and allows you to control the energy output without replacing other internal parts. This is especially relevant when you:
- Want to adjust your replica to field limits
- Switch between different gas pressures
- Want to maintain consistent performance across temperature differences
For correct operation, the NPAS system must work well with GBB Nozzles.
When should you choose an NPAS?
An NPAS is interesting when you want flexibility in your setup. Instead of fixed output, you are able to fine-tune the power accurately. This makes the system popular with players who want to optimise their replica for different playing conditions.
Correct adjustment is essential. Too open can lead to inefficient gas consumption, while too closed limits performance.
Installation and Adjustment
The installation of an NPAS requires technical knowledge of the nozzle and gas system. Because it directly affects gas flow, it must be carefully assembled and tested.
After installation, chronograph testing is necessary to safely and correctly set the desired energy output.
Material and Construction
Ra-Tech NPAS systems are typically manufactured from precision-milled steel or aluminium with accurate tolerances. This ensures consistent adjustment and durable operation under high pressure.
The adjustable core allows for controlled fine-tuning without structural modifications to the platform.
Frequently asked questions
What does NPAS mean?
Negative Pressure Adjustment System, an adjustable gas control mechanism.
Does an NPAS increase my FPS?
It makes FPS adjustable, both higher and lower within safe limits.
Is an NPAS universal?
No, compatibility depends on the platform and nozzle type.
Do I need to readjust my replica after installation?
Yes, chronograph testing and correct tuning are necessary.
With an NPAS from Ra-Tech, you get complete control over gas output and FPS adjustment within your gas blowback platform.

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