One of the great benefits of the AR-15 platform is the amazing amount of aftermarket support, especially in terms of stock options. The DoubleStar ACE Folding Stock Mechanism for AR-Type Stocks allows owners of rifles with Ace receiver blocks to take advantage of this support. The ACE Folding Stock Mechanism for AR-Type Stocks ensures that any AR-15 stock can be used on any Ace Receiver Block, including fixed and collapsible options. Constructed using 7075-T6 aluminum Total weight of 4.5 ounces Increased LOP of 0.75 inches Uses Boss stability features Mfg: Double Star