The Mini Aura helps you avoid the expensive task of replacing them by offering a digital night vision sensor cell, which won't die over time.
Mini Aura Digital Night Vision Monocular
For its size, this incredible digital night vision monocular is able to see deep into the night. With an estimated range of 30 meters (depending on lighting) this pocket night vision monocular will give you plenty of visibility for a variety of uses. It also offers a crisp black-and-white image unlike the fuzzy green images created by non-digital monoculars.