This assembly includes everything you need to add or replace your MPX or MCX stock with a folding buffer tube and the Magpul SL-K Stock
CAUTION: Many States and localities regulate the use and/or possession of collapsible and folding stocks. Use, or possession of this product in conjunction with certain other parts, may be illegal in some jurisdictions. It is YOUR responsibility to ensure your use of this product is in compliance with all Federal, State, and local laws and regulations.