Hiviz ARN21 Folding AR Back Up Sight - Black

The Hiviz ARN21 is a folding rear back up sight designed for the AR-15 platform. Built to mount directly to a standard Picatinny rail and fold flat when not in use, the ARN21 gives shooters a compact, dependable iron-sight aiming point that sits behind a red dot, holographic optic, or magnified scope without crowding the primary optic's sight line.

The ARN21 is purpose-built to pair with an A2-style front sight post, serving as the rear element of a complete backup iron sight (BUIS) system. Its folding design deploys with a positive lockup when called upon and tucks neatly out of the way when running a primary optic, so the rifle stays set up with iron-sight capability at all times. Finished in black to blend with most AR-15 rail systems and receivers.

Whether you are running a duty carbine, a training rifle, or a defensive AR-15 setup, the Hiviz ARN21 offers a straightforward, no-nonsense folding rear back up sight that complements your A2 front post and keeps you on target if your primary optic goes down.