The Leapers UTG Low Profile Dual Aiming Rear Sight is precision built from aircraft grade aluminum for superior durability"" and a spring-loaded Posi-lock design with side plunger release allows for easy flipping and folding of the sight. These AR 15 Iron Sights by Leapers are equipped with a dual aiming aperture that not only boosts your accuracy during normal shooting"" but is also ideal for moving target engagements as well as limited visibility shooting environments. Easily installed on a picatinny rail equipped AR platform"" the Leapers UTG Flip-Up Dual Aiming Sight guarantees zero retention with a Posi-lock plunger coupled with spring activated ball bearings. Make your rear sight as important as your optic with the Leapers UTG Dual Aiming Rear Sight for AR.