The KWA M4 Hop Up Nub is a replacement nub for use in any AEG hop-up unit. This nub is KWA Part 158, and is used in the KM4 RIS, SR7, and SR10, as well as in the CQR series.
Losing a hop-up nub will eliminate hop-up function, so replacing a lost part is critical for range and accuracy in any AEG.
KWA M4 Hop Up Nub Part 158 Features:
-Universal AEG fit
-Restore lost performance
All KWA parts are top-quality replacement or repair parts, and are the only parts recommended for use with KWA airsoft AEGs..