Pay in 4 interest-free payments of $98.75 Learn more
Ships within 48 hours · Estimated delivery Aug 7 - Aug 12
Developed in collaboration with SpeedQB
the M4P PRO model features advanced adjustment systems and locking mechanisms to ensure consistent tuning
Constructed from glass fiber-reinforced (GF) technopolymer
or premium custom projects
this blowback unit offers unmatched durability and reduced weight
RetroArms SR25 Spring SiCr with Progressive Winding — M140 Trigger Guards Developed in collaboration with SpeedQBThe RetroArms SR25 Spring SiCr with Progressive Winding M140 is a high performance main spring designed for SR25 and extended gearbox builds that require powerful and consistent compression. Manufactured from silicon chromium (SiCr) alloy steel, this spring offers superior resilience, reduced fatigue, and long term stability compared to standard carbon steel springs. The progressive winding design ensures smoother compression, reducing stress on the
US$ 29.99
US$ 187.50
US$ 427.50
US$ 643.50
