Maximize your rifles full potential with this spring guide upgrade from Prometheus. The full CNC aluminum build offers a lightweight yet extremely durable replacement part that is effective in minimizing stress on the gearbox, piston, gears, and motor inside your AEG gearbox. This heavy-duty spring guide allows the existing spring to be extended at a smoother and faster speed which results in a higher rate of fire in most AEGs. The function of the spring guide is to keep the spring in line allowing it to efficiently rotate on the shaft during high compression. To reduce spring stress and prevent internal breakage during high speed compression, this spring guide system comes equipped with steel thrust ball bearings. The universal design of this part allows players to utilize this high quality spring guide replacement to upgrade almost all AEGs with a metal gearbox.