3D printed accessories for hassle-free astrophotography

Made in Germany - Shipped from Germany

Inserts for the universal on-OTA mounting kit

Inserts for various compatible lenses or OTA for the “Universal on-OTA mounting kit for ZWO ASIAIR Pro or Plus with a belt drive for ZWO EAF

(use the arrows on the left and right sides in the middle of the frame to scroll through pictures)

Additional inserts for those customers who already purchased the "Universal on-OTA mounting kit for ZWO ASIAIR Pro or Plus with a belt drive for ZWO EAF". Insert can be either downloaded as STL files or ordered as printed without or with according belt and pulley which fits the selected lens or OTA

Please make sure that you have the right size of the hexagon rings.This size has been pre-selected for you when you purchased the kit for the first lens or OTA. Most lenses fit into the small hexagon rings. The large hexagon rings are currently needed for:

  • Canon EF 100-400mm f/4.5-5.6L IS II USM
  • Canon EF 70-200mm f/2.8L IS USM in versions I, II or III
  • William Optics RedCat 71
  • Askar ACL200

You can use any other lens or OTA with large or extra-large hexagon rings. If you ordered a kit with smaller hexagon rings before, you need to order larger hexagon rings in addition to the inserts, please contact us for more information about this.

Optionally, you can order inserts along with the pulley and the belt for the select lens for an additional price. The kit uses standard GT2 or T2.5 profile belts and pulleys. It might be simpler and even cheaper to buy these parts on Internet or in a shop in your country. We do not make money reselling belts and pulleys. It is just a convenience service provided for existing customers. Please contact us to find out the right size for the belt and pulley for the lens or OTA you want to use.

Moreover you can also select the download-only variant of this product. With this, you will get two STL files and instructions how to 3D-print them. This variant is provided for free. Please keep in mind that in this case you need to buy the belt and the pulley on your own. Sizes for the used belts and pulleys are listed on the page with assembly instructions.


If you have questions, feedback or suggestions for custom changes, please contact us using this form.

8 in stock (can be backordered)


VAT exempted according to UStG §19
Delivery Time: ca. 3-4 workdays
Additional costs (e.g. for customs or taxes) may occur when shipping to non-EU countries.

8 in stock (can be backordered)

type of inserts for OTA or lens included. You can order additional inserts separately
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