These 1.25" Svbony 66 degree astronomy eyepieces are blackened for increased contrast, preventing internal reflections. Anti-reflection fully multi-coated optics ensure bright and clear high-images at any magnification, with true color rendition. Fixed folding rubber eye cup allows easy use with or without eyewear Svbony astronomy eyepiece body is made of aluminum. A two-step anodizing process results in a beautiful matte finish that resists reflections and glare Sturdy anodized aluminum barrels are threaded for any 1.25" filters Suitable for observing the surface of the moon, planets, nebulae, star clusters, diffuse nebulae and other celestial bodies etc Specifications MODEL F9157A F9157B F9157C F9157D Focal Length 6mm 9mm 15mm 20mm Barrel Size 1.25" 1.25" 1.25" 1.25" Eye Relief 16mm 16mm 16mm 16mm Apparent Field of View 66° 66° 66° 66° Filter Threads Standard 1.25" Filter 1.25" Filter 1.25" Filter 1.25" Filter Coating Fully Multi-Coated Fully Multi-Coated Fully Multi-Coated Fully Multi-Coated Structure Design 5-elements in 3 groups 6-elements in 4groups 4-elements in 3 groups 5-elements in 3groups Rubber Eye Guard Yes Yes Yes Yes
