A Barlow lens offers an easy and economical way to increase the magnification range of your eyepieces by doubling the magnification of any eyepiece in use.
The Celestron Ultima series Barlow is an air-spaced, 3-element apochromatic design with a 27mm clear aperture. This lens has full multicoatings and is quite small and lightweight[weighs 0.31 lb (141 g) with length of 2.7" (7.0 cm)].
