Optics are vastly superior to iron sights until those optics malfunction or fail.

In the event of optic failure, backup iron sights (BUIS) offer a critical redundancy in the AR platform. Some BUIS can be deployed instantly. With a press of a button the sight flips up and locks into place, allowing an operator to continue with the mission and stay in the fight.

Scroll the gallery of iron sights above and check out more on the iron sight mentioned below.

A.R.M.S. #40 L-F/#40 L Combo

This front and rear sight pair offer a low profile in the folded position. The sights are spring loaded and held in place by a quick-release lever that also ensures the sights are not accidentally deployed. These sights lean slightly to the rear, so they fold back in the correct position if accidentally dropped. The rear sight has dual apertures for different engagement distances. (armsmounts.com; 508-584-7816)

AT Flip Up Combo

Flip Up Combo from American Tactical (AT) is an all-metal sight set for use on AR rifles. The rear sight has two apertures and is fully adjustable. The front sight of the system has an adjustable post. AT offers sets for ARs with flattop uppers and railed gas blocks as well as ARs with free-floating rails on the same plane as the upper. (americantactical.us; 800-290-0065)

Blackhawk Folding Sights

Delivering top performance with minimal bulk, the BlackHawk folding sight system delivers when it matters. With a push of a button the AR-15 folding rear sight springs up when needed. The front sight, which has an adjustable center post protected by side wings, springs into place just like the rear. Both are constructed with a polymer base and aluminum posts. (blackhawk.com; 800-379-1732)

Diamondhead D-45 Integrated Sighting System

The D-45 Integrated Sighting System features 45-degree-offset swing sights. All an operator needs to do is flip out the sights and roll the AR 45 degrees counter-clockwise. The rear sight stows under the eyepiece of a scope and features dual apertures with 0.5-MOA adjustments. The front sight accepts all standard A2 front sight posts. (diamondhead-usa.com; 413-739-6970)

GG&G 45 Degree Transition Sights

Engaging targets at close range is easier with GG&G’s 45 Degree Transition Sights. The front and rear combo set are offset at 45 degrees so all an operator does is cant the rifle or carbine to quickly get on target and continue firing. Made of 6061-T6 billet aluminum, the sights install on most Picatinny/Weaver rails. (gggaz.com; 800-380-2540)

Guntec Thin Profile BUIS Sight Set

Made of lightweight yet rugged T6 aluminum with steel inserts, the Guntec Thin Profile BUIS Sight Set features a push-button design that locks the sights to prevent them from folding down during use. This sight set installs on any flattop receiver and Picatinny rail and is designed for same-plane rail heights. (guntecusa.com; 480-478-4517)

Magpul MBUS Pro LR

Built with all-steel construction, the MBUS Pro LR features elevation adjustments to accurately engage targets at variable distances. The unit offers no-tool adjustments in a compact package. Positive detents keep the MBUS Pro LR at standard AR sight height when deployed and low profile when stowed. (magpul.com; 877-462-4785)

Mission First Tactical BUPSWF

The Back Up Polymer Flip-Up Front Sight with standard iron sight elevation adjustment (BUPSWF) features a shroud that shelters the front post blade from debris and impact damage when not deployed. The sight mounts onto any Picatinny rail and accepts any standard front post blade. The BUPSWF sight is made of reinforced, super-tough polyamide. (missionfirsttactical.com; 267-704-0001)

PRI Flip Up Front Sight

The PRI Flip Up Front Sight fits 0.75-inch-bore-diameter barrels, is simple to install and bolts on with ease. With the PRI sight folded down, the shadow cast on an optic from a fixed sight is eliminated. The circle hood also helps increase target acquisition. The base is constructed of 4140 cast steel and the post is made of T6-6061 aluminum that has been hardcoat anodized black. (precisionreflex.com; 419-629-2603)

Promag AR-15/M16 Flip Ups

The Promag rear and front sight system features a spring-loaded release for quick access. The rear sight has two apertures and is adjustable via a knob and the front sight has a wing-protected adjustable post. Made from T6 aircraft-grade aluminum with a black phosphate mil-spec finish, both mount to most Picatinny/Weaver rails. Polymer versions are also available. (promagindustries.com; 800-438-2547)

UTG Mil-Spec Sub-Compact Rear Sight

The UTG Mil-Spec Sub-Compact Rear Sight is fully adjustable for windage and elevation. Made of aluminum and steel
with a matte black finish, the rear sight offers a spring-loaded detent for positioning and repeatable adjustments. The sight is the exact height required for co-witnessing with a standard mil-spec-style front sight. (leapers.com; 734-542-1500)

Yankee Hill Machine 9835-H Flip Up Front Sight

The YHM-9835-H flip-up front sight is convenient as well as versatile with a built-in bottom Picatinny rail. The built-in gas block has a bore diameter of 0.75 inches and is completely made of steel. The unit is available with either a round, hooded front sight guard for fast and accurate sighting or a standard-style front sight guard. (yhm.net; 877-892-6533)