Orion 05594 2-Inch 13 Percent Transmission Moon Filter (Black) Helps reduce the bright glare of the Moon so you can see more lunar detail and surface features with your telescope 2 inch Moon filter with metal filter cell construction threads directly into the barrel of a 2 inch telescope eyepiece Especially useful for large aperture telescopes through which the bright Moon surface can be overwhelming Transmits just 13 percent of the incoming light to your eye, enhancing your view Neutral filter will not alter the natural color of the Moon in your views