Vortex BH-2354 Holder for CR-2354 Battery lets you be prepared with a backup battery. The Vortex Battery Holder mounts conveniently on a Picatinny rail. The Vortex Spare Battery Holder holds one CR-2354 battery, keeping your spare power supply close at hand in a waterproof, dust-free chamber. The cover opens with a simple turn via the coin slot on top, and is wired to the Vortex Battery Case so it can’t get lost. The SPARC red dot scope uses the Vortex CR-2354 Battery Holder.