SVBONY 68 degree ultra wide long eye relief eyepiece with a comfortable wide field for planetary observing,Super wide 68 degree apparent field offers expansive views of the moon;star clusters;and the Milky Way. It can be used in any astronomical telescopes that fits for standard 1.25" eyepieces. 68 degree ultra wide FOV Comfortable ultra-wide field, get bright and sharp viewing. Fully multi coated lens without introducing additional chromatic aberration; make image more sharper. Broadband green film optical glass. Chromatic corrected; Soft rubber eye guard Fold down soft rubber eye guard is more comfortable for eyeglass wearers Specifications:Structure design:4-elements in 3 groups (9mm) Eyepiece series:68 degree ultra wide eyepiece Focal length:9mm Barrel size:1.25" (31.7mm) Eye relief:17mm Apparent field of view:68 degree Lens material:optical glass lenses Body material:fully metal Filter threads:standard 1.25" filter thread Package includes: 1xSVBONY 1.25" ultra wide 15mm eyepiece 2xSVBONY lens cover. The SV221 diagonal mirror can protect the eyepiece from being scratched and not damage the service life of the eyepiece. Large screw design. Easy to use, locking eyepiece installation is easier and more stable. The SV221 diagonal mirror has M28.5x0.6mm thread, standard thread size, you can install 1.25 inch filter. The SV221 main mirror shell is made of precision molded ABS plastic, and the lens barrels at both ends are precision machined from aluminum, which will not be easily damaged.