The wide-angle eyepieces of Celestron's Luminos series offer a comfortable 82 degree field of view. Adjustable eyecups with an ultra-flat design for spectacle wearers. Parfocal eyepieces - little or no refocusing is required when switching between different magnifications. Filter thread for 1.25" filter. Polished and anodised aluminium sleeve - scratch resistant. Rubber ring for secure hold and comfortable adjustment of the eyecup. FIRING DIMENSION: 15 mm FACING FIELD: 82 ° EYE DISTANCE: 17 mm DIAMETER OF FIELD Aperture: 26 mm COATING: Fully Multi Coated OPTICAL DESIGN: 7 lenses ADJUSTMENT DIAMETER: 1.25" (31.75 mm) PARFOCAL: Yes WEIGHT: 340 g