It is an invaluable aid to centering guide stars and astrophotography target objects. Relatively high-power 6mm focal length telescope eyepiece with myriad uses is a welcome addition to any astronomer's accessory case. Folding down and removable rubber eye guard for wearing glasses and comfortable viewing as well as blocking stray light to increase the brightness of image. 16mm long eye relief, provides comfortable long term viewing for people with or without glasses. This 3x Barlow lens allows you to triple the magnification of any 1.25" eyepiece and deliver stunning image quality without adding a long reach between the telescope and eyepiece. The magnification of the Barlow lens is 3X, which can magnify the image without the Barlow lens by 3 times. You can see more details of the moon and planets, and the image is clear, making your observation more comfortable. The blackening of the edges of the Barrow lens and the internal blackening process can minimize the reflection of light during the refraction process, maximize the saturation and contrast of the image color, and make the image edges clearer. 1.25in Diagonal fits telescopes with 1.25in focusers. Accepts standard 1.25” eyepieces, filters, Barlow lenses and other accessories with a 1.25in insert barrel. 90° Viewing Angle, for more comfortable overhead viewing through refractor and Cassegrain type telescopes. Upright Image. Correct upside down and left right reversed image. It will look like trying to read a sign in a mirror. Suitable for space viewing, for there is NO upside down or right side up in space. Brass Compression Ring. Brass lock Screw for eyepiece or adapter and brass Compression rings features more precision and prevent barrels or the surface of eyepieces from marring and scratching.