This is a soft brush made to remove dust from optical surfaces. It has soft nylon bristles that will not damage your lenses.
The brush is really conveniently sized. It is about 4 7/8" in total length. The handle is about 3.6" long and the brush itself is about 1 1/8" long.
Always store the brush in a plastic bag when not in use and clean it completely before using it on any optical surface.