Component parts for firearms; Firearm attachments, namely, triggers, trigger guards, firing pins, and lower receivers for attaching to firearms; Triggers for firearms; Safety selectors for firearms; Firing pins for firearms; Trigger guards for firearms; Trigger kits for firearms including hammer, disconnector, safety selector, springs, and assembly pins; Lower receivers for firearms; Lower receiver kits for firearms including lower receiver, trigger, hammer, disconnector, magazine release button, magazine release, bolt catch, safety selector, buffer tube, buffer and spring, receiver end plate, castle nut, grip, springs and assembly parts and assembly pins, and front and rear takedown pins; Adapted cases and shoulder straps for firearms