Features: The "Variable" function allows you to adjust the length of the adapter to change the magnification (and therefore image size) for a perfect shooting composition. Suitable for telescopes with standard 1.25inch eyepiece ports. The thread of the 1.25inch lens barrel can accommodate a standard 1.25inch eyepiece filter. 3. Laser Sculpture scalability and repeatability expansion ratio. 4. Built in protective pressure ring to prevent scratching the appearance of the eyepiece tube This kit is suitable for: 2. Eyepiece projection and variable eyepiece projection In this imaging method, the eyepiece is used to increase magnification. The eyepiece is located between the camera and the telescope. The eyepiece projects the image onto the camera sensor. The size of the projected image increases with distance, similar to a flashlight beam. By using a "variable" projection adapter, the projection distance can be changed. This will change the magnification of the system, making you more flexible when composing. It can be seen as a 'fine' zoom in control. The 'coarse' magnification change is achieved by replacing the eyepiece. Eyepiece projection is commonly used for imaging the ground, moon, and planets, as well as at any time when higher magnification is required to display details. Important reminder: Reflective telescopes typically require the use of magnifying glasses 3. Refractive telescopes usually require the use of extension tubes The diameter of the upper tube of the eyepiece cannot exceed 42mm. The package includes: SV112 Variable Eyepiece Projection Adapter 1.25inch Prime Focus adapter 1.25 "Focus Ring Allen wrench Plastic spiral box