With this diagonal, you can match the orientation of the star field with standard star maps and charts. It produces an image that is upright but reversed from left to right. This diagonal is suitable for daytime terrestrial viewing and nighttime astronomy applications with telescopes or spotting scopes. Features - Color: Black - Size: 8.50 x 3.50 x 4.50 cm / 3.34 x 1.38 x 1.77 inch - Material: Plastic, glass - Note: Screw style may vary - Standard 0.965 inch diameter fits 0.965 inch eyepiece and telescope focuser - Designed for refractor and catadioptric telescopes; not intended for reflector telescopes - Wide 90-degree angle allows comfortable viewing from the refractor telescope stand by looking down at a natural angle - Easy to install and use: insert the silver end into the 0.965 inch telescope, and secure a 0.965 inch eyepiece at the other end using the screw - Constructed from durable materials, sturdy and resistant to damage Packing List 1 x Zenith Mirror