The Push Button Folding Mechanism is machined from aerospace grade aluminum with locking parts made from 12L14 steel! Gated push button protects against accidental stock release. By inverting the FSM-PB you can set-up the stock to fold left or right. Push the button to extend the stock and push the button to fold the stock. Works with all ACE Modular stocks.

Note: This item does not work with HK series receiver blocks.