Upgrade springs designed by AirsoftPro for the new generation of precision rifles are made from durable, heat-treated spring steel.
Note! Older AirsoftPro springs were significantly overpowered, but the nominal power of the newer production batches is closer to reality. A skilled technician can still achieve slightly higher muzzle velocities than the nominal rating with these new springs.
Inner diameter: 9mm
Outer diameter: 13mm
