Blackout Defense 300 Blackout 13.9" Pistol Length Gas Forward Assist Upper Receiver

TacFire AR-15 .300 Blackout Unassembled Upper Receiver Kit - 5"

ALEXANDER AR15 STANDARD UPPER - 300AAC 16" BLACK

LANTAC SF15 Recon Complete Upper Receiver 300 Blk 16"

CMMG 30BC40AMB Resolute MK4 300 Blackout 16.10", Midnight Bronze, M-LOK Free-Float Handguard for AR-Platform (No BCG or Charging Handle)

Wraithworks Billet Slick Side AR-15 Upper Receiver - Black | No Forward Assist or Brass Deflector

Patriot Ordnance Factory Wonder 13.75 300 Blue Titanium Mid Length Upper

CMMG BANSHEE MK4 UPPER SUPP'D 300BLK 6.5 BLK