Neutral Density Filter 2" ND 0.9 Features ND 0.9 Density, 13% Light Transmittance Even Reduction of Light Intensity Works Across Entire Spectrum Enhances Viewing of Bright Objects Ideal for Use on 4" or Larger Telescopes Ideal for viewing bright objects in the nighttime sky, the Explore Scientific Neutral Density 0.9 Filter is compatible with telescopes featuring a 2" eyepiece. This solid ND 0.9 filter transmits 13% of light across the UV, IR, and visible spectra, and cuts down on visible glare, without affecting color fidelity. It is particularly well-suited for observing or photographing the Moon with any telescope 4" or larger, and can also be used for splitting close double stars where one of the binary pair far exceeds the other in brightness. Color Filter #ND96 Moon Filter (0.9 density; 13% transmission)