Rear Back-Up Sight

Rear Back-Up Sight

The RBS is an advanced, dual aperture, durable and low-profile auxiliary rear sight. It can be used with any front sight and was designed for more accurate aiming and faster target acquisition. Windage is easily and quickly adjusted without tools.

RBS is readily mounted on any 1913 Picatinny rail, making it ideal for use on M4 / AR-15 / M-16 platforms and on the FAB DefenseĀ® K.P.O.S.


Can be used as primary or back-up sight

Ergonomic angel-wing-shaped shroud helps center the image with any front sight, and when used with a matching FAB DefenseĀ®  FBS Front Back-up Sight, 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

Link to parts manufacturer
no data
no data