Optical Glass: This dielectric 90° diagonal mirror is crafted from premium optical glass that ensures high clarity and sharpness for clear, distortion- views, enhancing your stargazing experience Dielectric Coating: Featuring a dielectric coating, this diagonal mirror maximizes light transmission, boosting brightness and contrast for more vivid and detailed observations, even under low light conditions Perfect for Beginners and Experts: Whether you're a beginner exploring the stars or an experienced astronomer, this diagonal mirror is designed to offer a comfortable and efficient viewing angle with ease of use for any skill level Versatile Compatibility: The 90° diagonal mirror is compatible with a wide range of telescopes and eyepieces, making it an ideal accessory for different optical setups and ensuring an ergonomic, upright viewing experience Compact and Lightweight: This diagonal mirror is lightweight yet sturdy, offering portability and ease of use without compromising on quality, making it perfect for outdoor stargazing trips, camping, or backyard observation