The HS507C will run up to 10 years on a single battery on setting 6, dot only. RMR compatible: This has the RMR footprint, so it is compatible with pistols that have slides or mounts that can take the RMR. 2 MOA Dot; 32 MOA Circle. Up to 50,000 Hours Battery Life (Setting 6).
12 Brightness Settings; 10 DL & 2 NV Compatible. Parallax-free & Unlimited Eye Relief.What that means is if you order. It depends on where you live.