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Primary Weapons "Ratchet Lock" castle nut and end plate.  Fits Mil-Spec & Commercial size buffer tubes.  

The new Ratchet-Lock Design eliminates the need for staking the AR-15 castle nut and gives a rock solid lock up while being able to remove it easily if needed in the future.

The central QD sling swivel mount allows for neutral positioning of your firearm with multiple sling configurations.