The Barlow lens is named after Peter Barlow. He developed the achromatic focal extender in the 1830s to assist in the observation of close double stars. The Barlow lens made the double stars appear wider apart making accurate measurements of their separation easier. Today, the same design allows us to increase the magnification of any eyepiece in order to achieve the best view possible from your telescope.
The Bintel Barlow 2x is fully multicoated for maximum contrast. Just insert it into your telescope’s focuser (or diagonal), and slip the eyepiece into the Barlow lens. A Barlow lens is a great way to squeeze more magnification out of your telescope without buying lots of eyepieces, and also allows you to use longer focal length eyepieces with nice big, comfortable eyelenses to provide higher powers.