A firearm stock that can be folded or collapsed to reduce overall length for storage or transport.

Uses high-pressure gas to cycle the action, rather than recoil energy.

Adjustable metal aiming devices on firearms, consisting of a front post and rear notch, used without magnification.

A mounting system for attaching optical sights to rifles.

Firearm mechanism where a sliding fore-end (foregrip) is moved back and forth to eject spent casings and chamber a new round.

Select fire is a fire selector mechanism on a firearm that lets the shooter choose the firing mode, such as semi‑automatic, burst, or fully automatic.

A pistol barrel with external helical grooves allowing the attachment of a suppressor or other muzzle devices.

A straight, cylindrical ammunition container that feeds cartridges into a firearm's action via gravity or a spring.