Firm locking; SV223 diagonal mirror has a clicklock locking mechanism; just turn the clicklock to securely fix the accessory; ensuring the eyepiece is installed and used stably; not easy to fall off Coating: 99% Reflectivity SV223 diagonal mirror has metal high reflective dielectric coating Surface accuracy: 1/10λ High-quality machining out of the aluminum; SV223 star diagonal is composed of High-quality aluminum elements; chic; light and stable; internal antireflection baffling for highest contrast 90 degrees design; SV223 star diagonal has a 90 degrees refraction angle; providing a better observation experience when visually observing Features: The 1.25-inch diagonal dielectric mirror has a click-lock locking mechanism to ensure stable installation and use of the eyepiece; 99% reflective dielectric coating, large light transmission, and good imaging effect; carbon fiber cover design, chic, light and stable; with 90-degree refraction angle, providing a better observation experience when visually observing;The brass pressure ring design is not easy to damage the eyepiece and other telescope accessories; the 2-inch to 1.25-inch adapter is convenient for installing accessories of different calibers, and can be used for astronomical scene observations such as planets and deep space.Specifications:Brand: SVBONY Model: SV223 Size: 2inch Optical Design: Mirror Diagonal Inner Connection (Lens Sided): Thread M48x0.75 Outer Connection (Lens Sided): Barrel 2inch Inner Connection (Eyepiece Sided): Clamp 2inch Reflection Surface: Dielectrically Coated Reflectivity: >99% Image Orientation: Erect Image, Mirror Inverted Optical Length: appr. 109.1mm Clamping System: Clicklock Deflection Angle: 90° Clear Aperture: 43mm Material: Metal Thickness of Mirror: 11.5mm Net Weight: 573.7g/20.24oz. Package Includes:1XSV223 2" 90 Degree Clicklock Dielectric Diagonal Mirror; 1X2inch to 1.25inch Adapter ;1X M4 Screws ;1X Dust Cap 1X Dust Plug