Build and customize lower receivers using the Smith & Wesson M&P AR-15 Lower Parts Kit. The lower parts kit includes bolt catch, bolt-catch plunger, bolt-catch roll pin, bolt-catch spring, buffer retainer, buffer-retainer spring, disconnecter, disconnecter spring, hammer, hammer pin, hammer spring, magazine catch, magazine-catch button, magazine-catch spring, pistol grip, pistol-grip lock washer, pistol-grip screw, pivot pin, pivot-pin detent, pivot-pin detent spring, selector, selector detent, selector-detent spring, takedown-pin, takedown-pin detent, takedown pin detent spring, trigger, trigger guard, trigger-guard roll pin, trigger pin and trigger spring. This is the updated parts kit. Made in USA. Manufacturer model #: 1085634. Build and customize lower receivers Mil-spec parts needed for a stripped lower receiver