This neutral density filter transmits light uniformly across the entire visual spectrum. It serves as an excellent filter to reduce glare when observing the Moon with larger telescopes. This filter may also be employed in the splitting of close double stars where one of the binary pair significantly exceeds the other in brightness. The special purpose filter features a 13% light transmission. Threaded for and compatible with all Meade Series 4000 and Series 5000 eyepieces. Product carries a full one year Meade factory limited warranty.