Redesigned to make it easier to power and use, the Explore Scientific Illuminator II Red LED Finderscope Illuminator now runs on two user-supplied AAA alkaline batteries that are not only easier to find than the small coin batteries previously used, but last longer. This updated model also features variable-intensity brightness control over the red illumination so you can carefully control how much the reticle is illuminated to make it easy to see without affecting your night-adjusted vision. Made as an upgrade for their straight VFEI0850-01 and right-angle VFEI0850-RA finderscopes, the Illuminator II will also work in most other illuminated finderscopes that use standard illuminators, and installs using the same mounting threads.