Feyachi S09 Viseur de secours en fer – Viseur rabattable pour rails

Attaching an optical sight either prevents the use of iron sights or results in a setup that produces a front sight "shadow" on the optical image, and/or results in problematic transitions from optical to backup iron sights.
Rapid Transition Sights (RTS) provide shooters with the quickest possible transition between longer- and closer-range target acquisition, greatly increasing their efficiency and effectiveness in battle and competition.

This unique offset position makes transitioning from optical to iron sights simply a matter of quickly canting the weapon with your wrists and locking on to the target.
There's no removing a hand from the weapon or making a manual adjustment, and no cluttered field of vision or iron sights blocking the optical sight.
Just smooth, quick transitions that could mean the difference between winning or losing a competition, or more importantly-a gunfight.