Juggernaut Tactical is proud to introduce the Hellfighter Mod Kit, the perfect, ultra-fast California Compliant magazine lock solution for your AR-15. This comes after a year of engineering and countless attempts to make the best and simplest solution on the market. With this bolt-on solution (patent pending), you will be able to perform magazine changes faster than you ever thought possible. One of the features that sets Juggernaut Tactical apart is our modified quick-release takedown pin, which acts as a button to separate the upper from the lower just enough to disengage semi-automatic operation and automatically disable the magazine lock. Once your upper is separated and disengaged from semi-automatic operation, your magazine release is now operable. A simple tap closes the upper and re-engages the spring-loaded takedown pin and will quickly get you back in the fight. The Hellfighter Mod Kit is compatible with any Mil-spec AR-15.