Magpul PTS 120rd PMAG Mid-Cap for M4 / M16 / Masada / ACR Series Airsoft AEG. (Black)
This is the genuine Magpul PTS licensed 120 round no-winding P-MAG. Much higher capacity than the STAR 75 rounders and doesn't require any wining for the serious mil-sim players that requires stealth movement at the same time.