Alstar Astronomical 2"/M48-extension Tube Kit for cameras and eyepieces - Length 5mm 10mm 20mm 30mm M48x0.75 on Both Sides

Improve Focusing Problem: The extension tube has a M48x0.75 interior thread and a M48x0.75 exterior thread; elegantly solves the spacing problems in astrophotography and improve a series of focusing problems Variable Combination: The required spacing can be achieved by combining several extenders of differing lengths; Use this extension tube for getting the correct image scale or the exact spacing required for reducers or field flatteners Aluminium Alloy Material: All metal construction and anodizing aluminium process; resistant for long time use Eliminate Extra Light: The design of the internal thread can eliminate stray light and reflected light; making the image clearer and perfect 100 Percent Satisfaction: If you have any question with our product; please contact us freely