Here is a video from PTS Syndicate for the Tokyo Marui Recoil Shock M4, SCAR-L, and HK416D Series... "The PTS Enhanced Polymer Magazine, or EPM for short, is a new type of Polymer Magazine for airsoft rifles. The EPM is a truly unique magazine, inside and out. Externally it features a polymer shell, with recessed panels for better grip, and unique magazine well guides that reduce snagging when the magazine is drawn from and reinserted into pouches.

PTS Syndicate finally unveil their EPM version for the Tokyo Marui New Generation M4 and SCAR-L AEGs that have the blowback and recoil feature. This can probably fit the Marui HK416 NEGs as well... "The PTS Enhanced Polymer Magazine, or EPM for short, is a new type of Polymer Magazine for airsoft rifles.  The EPM is a truly unique magazine, inside and out.