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Heat-Treated Castle Nut


Castle nut upgrade for AR15 / M4

The Heat-Treated Castle Nut screws onto the AR15/M4 lower receiver extension (buffer tube) and keeps the receiver extension and lower receiver end plate secured in place. 

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The large notches allow for positive engagement with a castle nut wrench for proper installation and torque.  The smaller notches provide a location for the end user to stake the castle nut to prevent accidental loosening.

Finished in a Mil-spec manganese phosphate.

Made in the USA.

Technical Specifications

Platform: AR10, AR15, M4, M16, M110, SR25