Like each eyepiece in its series, the XW 10 eyepiece is designed specifically to provide ideal ground and astronomical observations with a telescope. It features fully multi-coated lenses to increase light transmission and color quality, high-refraction lanthanum glass elements for high-resolution images with minimal aberrations, and JIS Class 4 weatherproof construction for durability. Engineered using advanced computer simulation design technology, this eyepiece features a 70 degree field of view and 20mm eye relief.