F.A.B. FRBS Kit

Advantages:
Can be used as primary or back-up sight
Ergonomic angel-wing-shaped shroud helps center the image, it creates a precise optical tunnel that ensures more accurate aiming and faster target acquisition
Dual apertures are 3mm for longer eye relief mounting, low light, and faster target acquisition; and 1.5mm for shorter eye relief mounting and greater accuracy; each is instantly selectable to match conditions
Low folded profile is smooth and inconspicuous, and will not snag on gear, webbing, or brush
Instant spring-locked deployment mechanism will not slip, break or deform
No tools needed for easy, rapid windage adjustments, with positive detent locking
Made of extremely durable high-grade polymer and metal
Available in black, olive drab green, or flat dark earth
Compatibility:
All 1913 Picatinny rails