Filling the same mission requirement as the standard MS3 Sling, the MS4 can quickly switch between one-point and two-point configuration.

The MS4 maintains material construction and specifications identical to that of the standard MS3, but features two heavy-duty push-button QD sling swivels rather than the Paraclip. This modification allows compatibility with QD sling cups commonly found on lower receivers, receiver end plates, buttstocks, and many low-profile forward QD Sling mounts, including the RSA-QD.