Designed for use with PENTAX brand spotting scopes and with astronomical telescopes with appropriate 1 1/4" or 2" focusers. Ideal for both ground and astronomical observations, this eyepiece 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 high-performance eyepiece provides 20mm eye relief.

Lens Structure: 8 elements, 5 groups Real Field of View: Apparent Field of View: 70 Degree Eye Relief: 20mm Field Stop Diameter: 4.3mm Dimensions: 5.4 x 2.4 in. Weight: 14.3 oz. Notes: