LBE Unlimited AR Castle Nut – AR-15/M4 Buffer Tube

The LBE Unlimited AR Castle Nut secures the buffer tube to the lower receiver threading on AR-15 and M4 platform rifles. This standard castle nut ensures proper retention of the buffer tube assembly and prevents loosening during firing. Castle nuts require periodic inspection and may need replacement during stock upgrades, receiver builds, or when switching between commercial and mil-spec buffer tubes.

Manufactured from steel with a manganese phosphate finish for corrosion resistance. Installation requires an AR-15 armorer's wrench to torque the nut properly and a staking tool to secure it against the receiver end plate. This is a standard mil-spec dimension castle nut compatible with mil-spec buffer tube threading.

• Part Type: Castle Nut
• Compatible Firearms: AR-15, M4, and AR-15 pattern rifles with mil-spec buffer tube threading
• Material: Steel
• Finish: Manganese Phosphate
• Installation: Requires AR-15 armorer's wrench and staking tool
• Includes: One castle nut