The Nightforce Optics Flip-Up Objective Lens Caps are constructed to Nightforce’s exact quality requirements by Tenabraex and offer an incredible level of protection and durability. The caps are designed for long-lasting use in rugged conditions and attach to the objective bell through the use of an adapter that threads into the scope housing. Once attached, the caps open easily with finger pressure and can be locked back with extra pressure. This particular flip-up lens cap model is made for the company’s first focal plane ATACR riflescope. Mfg: Nightforce