The Lumicon LumiBrite Dielectric Coated Diagonal reflects 98 percent of the light from the telescope's primary optics directly into your eyepiece. Its single 1/8 wave precision polished surface is superior to the three surfaces of prism diagonals. The Dielectric Coating is smoother and even more durable than a standard aluminum coating, providing maximum image contrast.
Lumicon collimates each and every Lumicon Mirror Diagonal it sells with a double-pass collimator, ensuring that the light reflected from the diagonal is perfectly perpendicular to the optical axis of the telescope's primary optics. Threaded for use with Lumicon's renowned light pollution blocking filters. Makes eyepiece-changing a breeze while using your Lumicon filter.