If you are looking for a solid CQB gun, then the SIG 516 is for you. With a full RIS system, it can support any accessories you want to add. The flip up sights give you quick target acquisition, and the retractable crane stock allows for easy maneuverability. The King Arms SIG is made to stand the test of time; the gearbox is full metal and reinforced. The metal hop up unit gives you the performance you demand. The engraved SIG trademarks give you the look and realism you want in an airsoft gun!