Featuring a wide 60° field of view and generous 18mm eye relief for comfortable glassing, the Pentax XF smc 12mm Eyepiece is designed for use with their 100, 80, and 65mm spotting scopes or any telescope or spotting scope that accepts standard 1.25" eyepieces. Extra-low dispersion lanthanum glass in the 6-element/4-group lens design provide a balanced image with minimal aberrations, while the proprietary smc anti-reflection multi-layer lens coatings prevent reflection for optimal light transmission. The eyepiece is constructed to be water resistant, easily withstanding light rain or dew. For digiscoping, there is a 30.5mm mounting thread under the removable twist-up click-stop eyecup for attaching your rings and adapters.