LBE Unlimited AR Essentials Kit, Includes Bolt catch plunger, Bolt catch spring, Bolt catch roll pin, Buffer retainer, Buffer retainer spring, Disconnector spring, Hammer spring, Trigger spring, Hammer pin, Trigger pin, Pivot pin detent, Pivot pin detent spring, , Takedown pin detent, Takedown pin detent spring, Selector detent, Selector detent spring, Trigger guard roll pin, Magazine catch spring ARESNTL LBE US Made AR essentials kits are appropriate for your next build and great to have on hand to service your favorite AR.