The Carson CS-20 C6 Compact Lens Cleaner with Nano-Particle Cleaning Formula is an easy to use way to keep your optics free from dust, dirt, fingerprints and grime. The soft tip is embedded with Carson's Dry Nano-Particle Cleaning Formula that is especially designed to keep your optics free from these contaminants. The other end contains a retractable brush that is gentle on your lenses. A built-in ring on the cap is included to attach your Cleaner to your keychain or carabiner. No batteries or AC power are required for use.