This erecting eyepiece flips the image you see right-side-up. As you may know, Reflector Telescope use mirrors to collect light which means they usually project an "upside-down" image. When you are looking into space, this is insignificant because there is no upside-down in Space. If you want to use you telescope during the day to look at things here on Earth, you will probably want the image flipped back the right way. This eyepiece is compatible with any telescope or optical device that uses a standard 0.965 inch diameter eyepiece. 1.5x Magnification Increase Use Your Reflector Telescope For Daytime Viewing Flips Images Right-Side Up Great Add-On For Telescope Beginners Magnification: 1.5X Port size: 0.965 inches Colour: black Material: plastic Package Contents: 1 * 1.5X Barlow Lens Only the above package content, other products are not included. Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.