Neutral density filters are excellent filters to reduce the overall brightness of an image to cut down glare while viewing bright astronomical objects like the Moon through a telescope. 
It retains the true color balance of the object.
This ND96 neutral density filter allows 25% of the visible light to pass through.
It comes with a standard 1.25" male filter thread (M28.5x0.6) so it can be screwed on to virtually any astronomy eyepiece or accessory that has 1.25" filter threads. It also features a standard 1.25" female filter thread on the other side, so it can be stacked with additional filters.
It comes in a protective plastic storage box.