The Action Army Piano Wire AEG Spring M140 delivers consistent performance and reliability for airsoft AEG rifles. Engineered with high-quality piano wire construction, this spring maintains excellent durability through extended use and repeated cycling. The M140 rating provides a balanced power output suitable for mid-range engagement distances, making it ideal for players seeking improved performance without excessive wear on gearbox components. Easy to install during standard AEG maintenance, this spring is a direct replacement for stock units. Perfect for upgrading your rifle's performance while maintaining reliability and longevity in the field.