Modern Carbine - The first of several MODs to come with the design as well as added details and improvements over time. small improvements made on this model compared to the previous version include : 

• Updated iron sight
• Holographic sight 
• Visible bolt
• Forward assist
• Slimmer and smaller feel
• Adjustment to the picatinny rail
• Fire selection
• Magazine release
• Weapon light 
• Suppressor (Optional)
• Enhanced grip for ease of use