SVBONY, The 40mm Plossl eyepiece is constructed with a 4-element design and provides a generous 40° field of view; perfect for wide-field moon observations; medium star clusters; offers a wide range of cloudy nebulae and deep sky targets. Soft rubber eye protection specially equipped with a bayonet mount and folds down for the comfort of people who wear glasses and protects the glasses from scratches. Fully multi coated lens telescope eyepiece with all black interior design; No introduction of additional color for higher magnification; Strong achromatic; Enhances details of Jupiter; Saturn; Mars; Venus and planetary filters. 31.75mm telescope eyepiece; standard diameter 31.75mm for all telescopes and accessories with this diameter; M28.5×0.6 filter thread for 31.75mm filter; rubber eyecup to fold over for comfortable viewing and protection from stray light. Portable and Durable Full metal design is sturdy and solid for long time use; Comes with a plastic case that is easy to carry and store; Makes a great birthday or Christmas gift.