Huma-Air FX Impact Valve Return Spring
HUMA-AIRHuma-Air FX Impact Valve Return Spring
1x Valve Return Spring:
This slightly weaker valve return spring can be used on any FX Impact equipped with the genuine FX Power Plenum. This spring has a bit weaker powercurve compared to the original valve return spring what will result in a bit longer valve opening time to get some more extra power out of your rifle.
It's great when you want to tune your FX impact for slugs or hybride slugs
1x NBR Buffer Ball
The rubber buffer ball is placed inside the spring and limits the stroke lenght of the valve.
Please note:
When using this valve return spring in the M3 or an impact where the 720 plenum kit is fitted the rubber ball should not be used. The new valve adjuster alrady has a rubber buffer installed and adding this ball will result in a reduced stroke and loss in power.