Features of Holosun HE507K-GR X2 Green Dot Reflex Sight. MRS: Circle Dot; 2 MOA Dot; 32 MOA Circle. Up to 50,000 Hours Battery Life (Setting 6). 12 Brightness Setting: 10 DL & 2 NV Compatible. Convenient Tray Battery Compartment. Parallax-free & Unlimited Eye Relief. Holosun HE507K-GR X2 Green Dot Reflex Sight.