The Orion Shorty Barlow Lens doubles the power of any telescope eyepiece. It has a multi-coated lens that lets in more light and allows you to enjoy higher-power, sharper images without eye strain.
I'm no astronomer, but I've used various telescopes since I was a kid and I've always found that the quality of the viewing experience comes down to which eyepiece you use. With that in mind, I was hopeful that the Orion Shorty Barlow would allow me a bit more magnification from my Orion Sirius Plossl 25mm eyepiece (used in my Skyquest XT6). I was really looking for increased magnification with the hope that I would not lose image quality. I am very happy with the results. I've mostly been using my telescope to view Saturn lately (May 2010) and the Shorty really pulls Saturn in nicely. And now that I know what a good job the Shorty does, I can feel comfortable purchasing additional eyepieces knowing the that shorty will give me double duty from them as well.