Made of high quality optical glass, the 1.25'' EF (EXTRA FLAT FIELD) eyepiece series is truly one of kind with a sharp, 60 Degree FOV with the 8mm, 12mm & 16MM, a 65 Degree FOV with the 19MM, & 53 Degree FOV when using the 27MM. Virtually free of pincushion and field curvature. Fully Broadband Multicoated optics bring out true color stars and sharpness. Air Spaced Blackened Lens Edges for enhanced contrast and brightness. Parfocal and smooth Twist Up eyecup, a nice feature for those who use eyeglasses. EF eyepiece series come with dust caps and Microfiber cloth.