Solomark 2inch Explorer Enhanced Dielectric Diagonal Mirror with 2inch-1.25inch Adapter - ENHANCED 99% REFLECTIVITY for Maximum View Brightness and Sharpness-Carbon Fiber Side Plates Explore the nature of the world -This 2inch mirror diagonal features sophisticated, Multi-layered dielectric coatings that provide an astounding 99% reflectivity for maximum view brightness and sharpness. High precision optical glass with 10mm thick mirror substrate. 100% carbon fiber side plates and Baffles is machine-threaded and anti-reflection process for high contrass Nosepiece barrel is threaded to accept 2" filters. 2 pieces of brass lock screws for eyepiece or adapter and brass Compression rings features more precision and prevent barrels or the surface of eyepieces from marring and scratching. Comes with a 2"-1.25" step-down adapter which allows to use 1.25" eyepieces and other 1.25" accessories. Endcaps included.