Anti-reflection devices have been used in military and police applications for many years to eliminating excess scope glare and hide any glint as to not give away your position. However, these devices have many more practical advantages for the everyday user. Eliminating scope glint can also be helpful in hunting situations as bright reflections can possibly scare away deer. It also is extremely helpful in keeping your glass clean from dirt and debris that can possibly scratch the lens. This anti-reflection device is made from anodized black aluminum and is easily installed by screwing it into the objective lens. This model only fits the Primary Arms SLx 25mm red dots.Features:Eliminates glare and glint off the front lensProtects scope lens from dirt and debrisMade from durable anodized black aluminumEasy to install