5.56x45mm NATO Upper Receivers

NBS AR-15 Assembled Upper Receiver

NBS 16" 5.56 Gov / SOCOM Midlength M-LOK Upper Assembly - Black

16" 5.56 NATO Lightweight Carbine M-LOK Complete Upper

Smith and Wesson Complete Uppers 5.56 16" Furniture Magpul PD Trade-In

Cloak Industries MFR 56 Belt-Fed Dual-Feed 16" Quick-Change AR-15 Upper - Black

Aero Precision AR-15 M4E1 Enhanced Upper Receiver - Kodiak Brown

One Horse 16" 5.56 SOCOM Midlength 1:7 M-LOK Upper Assembly

One Horse 16" 5.56 SOCOM Midlength 1:8 M-LOK Complete Upper

NBS 7.5" Slick Side Billet 5.56 Nitride Pistol M-LOK Upper Assembly

Obsidian Arms 15C Upper Receiver Billet Black Hardcoat

Aero Precision M4E1-E 16" Mid 5.56 Complete Upper, No Forward Assist, EM15 Handguard - Black

Aero M4E1-E Complete 16" Upper, 5.56 Mid Hanson Barrel, 15" Enhanced Handguard - Black

NBS Slick Side Billet Receiver & M-LOK Handguard Combo - 15"

NBS Slick Side Billet Receiver & M-LOK Handguard Combo - 4"

NBS Slick Side Billet Receiver & M-LOK Handguard Combo - 12"

NBS Slick Side Billet Receiver & M-LOK Handguard Combo - 7"

NBS Premium Series 14.5" 5.56 NATO Upper Assembly w/ CMT UHPR Mod 2 HDX

8 Pistol 5.56 Government M-LOK Upper Assembly

8" 5.56 Government Pistol M-LOK Upper Assembly

16 5.56 Black Nitride 1:9 Carbine M-LOK Government Upper Assembly

NBS 14.5 5.56 Phosphate + Chrome-Lined Carbine M-LOK M4 Upper Assembly

NBS 16 5.56 Phosphate Midlength M-LOK Lightweight Complete Upper

NBS 16 5.56 Phosphate Midlength M-LOK Lightweight Upper Assembly

16 5.56 Phosphate Carbine M-LOK Government Upper Assembly