A quality eyepiece providing a better image than those that come included with new telescopes 46 degree field of view significantly wider than Kellner and standard Ploessl eyepieces; eye relief: 31mm Multi-coating and Blackened Lens Edges for High Contrast: When observing with a telescope; it really all comes down to good quality eyepieces; these are just as important as the telescope itself 1.25 inch connector the eyepieces will fit in any telescope; rubber fold-down eyecups to protect against stray light A Large Range of Focal Lengths from 4 mm to 40 mm: These eyepieces provide you with a range of 19 focal lengths; so you are guaranteed to find the right magnification and increments for your telescope; and the best part all the eyepieces are parfocal ASIN B06XGSKG76 Item Weight 3.07 ounces Manufacturer Astromania Item model number SKU_AM_SPE40 Product Dimensions 3.24 x 1.89 x 1.77 inches Is Discontinued By Manufacturer No