WHAT DOES STERLING MK4 9MM CARBINE MEAN?

Survivability is improved from the addition of various modular armor protection schemes for the two the M60's turret and hull. The upgrades incorporate armor security with STANAG 4569 Level 6 safety plates to your frontal arc, passive and reactive armor panels and facet skirts and slat armor added to your bustle, protecting the rear of your turret