Lower Parts Kit made from only the highest quality Mil-Spec or better components. The SOLGW Bolt Catch and Safety Selector are a Mil-Spec AISI8620 investment casting per the USGI TDP. Their Safety and Takedown Pivot Detents are solid hardened Stainless Steel from KNS Precision Machine. SOLGW Magazine catch and Takedown Pivot Pins are machine from Mil-Spec AISI8620 per the USGI TDP, heat treated and coated per mil spec. Their Mag Buttons are made from steel per Mil-Spec versus the aluminum found in the majority of commercially available LPKs on the market. The Liberty Fighting Trigger is designed to give a consistent and crisp pull. They have created the perfect balance between proven mil-spec components and smooth grit free pull and break. The Hammer and Trigger have been treated in durable, corrosion resistant Nickel PTFE to reduce friction and maintain lubricity. The pull weight averages at 6 lbs, without any modifications that would compromise proper function. Best part is, it is Guaranteed for Life.