BROWNELLS - M4 Buttstock Wrench

BROWNELLS BUTTSTOCK WRENCH FOR CAR-15/M4

The Brownells Buttstock Wrench for CAR-15/M4 is a purpose-built armorer's tool designed for the installation, removal, and maintenance of collapsible AR-pattern carbine stocks. Engineered to engage all four notches of M4-style receiver extension nuts, this wrench provides positive, non-slip contact for efficient castle nut service while helping reduce the risk of damage to the receiver extension, lock nut, or lower receiver.

Machined from a single piece of heavy-duty steel, the wrench delivers the strength required for professional gunsmithing, armorer work, and firearm maintenance. Its dedicated four-tooth design transfers torque directly to the receiver extension nut, allowing secure tightening and removal without the slipping commonly associated with improvised tools.

In addition to its primary function, the wrench incorporates several useful armorer features, including a 1/2" square-drive opening for torque wrenches, a fixed-stock receiver extension remover, an integrated pry blade/screwdriver, and a hanging hole for convenient storage.

FEATURES

• Designed for CAR-15 and M4-Style Collapsible Stock Systems
• Four Precision-Machined Teeth for Positive Castle Nut Engagement
• Engages All Four Notches on M4-Style Receiver Extension Nuts
• Helps Prevent Slippage During Installation and Removal
• Transfers Torque Directly to the Lock Nut
• Integrated 1/2" Square Drive Opening for Torque Wrench Use
• Built-In Fixed Stock Receiver Extension Remover
• Integrated Pry Blade/Screwdriver
• Heavy-Duty One-Piece Steel Construction
• Convenient Storage Hole for Pegboard Mounting
• Made in USA

SPECIFICATIONS

• Brand: Brownells
• Brownells Part Number: 080000670
• Tool Type: Buttstock / Castle Nut Wrench
• Compatibility: M4-Type Receiver Extension Nuts
• Material: Hardened Steel
• Finish: Black Oxide
• Overall Length: 7-1/8" (18.1 cm)
• Construction: One-Piece Steel
• Steel Thickness: .312" (7.9 mm)

COMPATIBILITY

• CAR-15 Style Carbines
• M4 Pattern Carbines
• AR-15 Rifles Equipped with M4-Type Receiver Extension Nuts Featuring Four Square Notches

The Brownells Buttstock Wrench for CAR-15/M4 delivers the strength, engagement, and versatility required for professional AR stock installation and maintenance. With its precision-machined four-tooth design, one-piece steel construction, and built-in armorer functions, it is an essential tool for gunsmiths, armorers, and serious AR enthusiasts.

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