LWRCI's Skirmish Sights incorporate a host of practical features into a comfortably new design. All of the sharp edges on these low-profile sights have been rounded to prevent snags and cuts to the operator. The folded profile of the sight has been kept to only half an inch. The sights lock securely into the ""up"" position and are lowered by pressing the button on their left sides. The sights are constructed mainly of anodized 7075 aluminum and Nicorr-coated 4140 steel. These sight are a must have for any AR-15 / M-16. Mountable to any 1913 picatinny rail"" Skirmish Sights feature a locking helicoil which requires no additional thread lock for installation and will stand up to thousands of rounds of recoil and rugged use.