FAB Defense FX-FRBSOSLHB Front/Rear Offset Flip-Up Iron Sights 1913 Picatinny Black

The FAB Defense FX-FRBSOSLHB is a front and rear offset flip-up iron sight set designed as a low-profile backup aiming solution for rifles, carbines, and any firearm equipped with a 1913 MIL-STD Picatinny rail. The pair is positioned to the side of the optic rail, eliminating co-witness interference with red dots, holographic sights, and magnified optics mounted on the main rail.

Built by FAB Defense for rugged field use, these sights feature durable flip-up mechanics that deploy quickly and lock positively into the firing position. The black finish keeps a low visual signature, while the offset mounting design preserves rail real estate for primary optics or accessories.

Per the manufacturer's specifications, the unit measures approximately 52 mm long, 32 mm wide, and 14 mm tall, making it a compact companion to any rail-mounted optic setup. Whether you run a flattop AR-15 or M4, an AK-platform rifle with a 1913 Picatinny top cover, or any other 1913-spec carbine, the FX-FRBSOSLHB provides reliable backup iron capability exactly where you need it.

Clamp the set to the rail in seconds, flip the sights up when the primary optic goes down, and knock them flat when you don't need them - all without removing the offset unit from the rail.