Stern Defense 4 Inch Mod4 M-LOK 4" Barrel Upper Receiver, 45 ACP - SD4INCHMOD4MLOK4INCHBARREL45AC

This Stern Defense upper receiver features a 4-inch barrel chambered in 45 ACP and includes M-LOK mounting slots for accessory attachment. The Mod4 platform design provides a complete upper assembly solution for AR-15 style builds. Precision-machined steel construction ensures durability and reliable performance.