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IMPORTANT: Our store is located in Canada. All orders that include products manufactured outside of Canada or USA will be subject to tariffs and duties, regardless of the order value. US customers are responsible for all applicable duties and tariffs, and those will be billed by the carrier, except for the Lacerta upgrade kit, for which we collect them at checkout.
IMPORTANT: Our store is located in Canada. All orders that include products manufactured outside of Canada or USA will be subject to tariffs and duties, regardless of the order value. US customers are responsible for all applicable duties and tariffs, and those will be billed by the carrier, except for the Lacerta upgrade kit, for which we collect them at checkout.
Starlight Instruments 3.5" Adapter for TEC Large Refractors

Starlight Instruments 3.5" Adapter for TEC Large Refractors

by Starlight Instruments
SKU SI-A35-503TEC
$200.00 - $200.00
$200.00
$200.00 - $200.00
$200.00
Price Match Policy!
  • Connects 3.5" Feather Touch Focusers to TEC Large Refractors
  • Precision-Machined Aluminum Construction
  • Ensures Perfect Optical Alignment
  • Non-Threaded Interface Design
  • Made in the USA by Starlight Instruments
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  • Description
  • FAQ
  • Downloads
  • Warranty

  • Starlight Instruments 3.5" Adapter for TEC Large Refractors

    This Starlight Instruments adapter provides the essential, high-precision mechanical interface for mounting a 3.5" Feather Touch focuser onto a large Telescope Engineering Company (TEC) refractor.

    Secure Your 3.5" Feather Touch Focuser to a TEC Refractor

    This adapter creates the critical link between your TEC refractor's optical tube and a Starlight Instruments 3.5" Feather Touch focuser. Designed specifically for a precise, non-threaded fit, it ensures your focuser is held in perfect alignment with the optical axis, which is fundamental for achieving sharp, high-contrast images.

    Machined from a single piece of high-grade aluminum, the adapter eliminates any potential for flexure, tilt, or image shift, even with a heavy camera and filter wheel attached. Its build quality provides a solid, reliable foundation for your imaging train, reflecting the same commitment to precision that defines Starlight Instruments' focusers.

  • What is the Starlight Instruments 3.5" Adapter for TEC Large Refractors used for?

    This adapter is a custom-machined component that allows you to securely attach a Starlight Instruments 3.5" Feather Touch focuser to the rear cell of a large Telescope Engineering Company (TEC) refractor. It provides a stable, perfectly aligned mechanical connection between the telescope and the focuser.

    Which focusers are compatible with this Starlight Instruments adapter?

    This adapter is designed exclusively for the Starlight Instruments 3.5" Feather Touch focuser family. It will not work with 2-inch, 2.5-inch, or 3-inch models, nor is it compatible with focusers from other manufacturers.

    How does this adapter attach to a TEC refractor if it has no threads?

    This adapter utilizes a non-threaded, slip-fit design specific to certain large TEC refractors. The focuser body typically inserts into the adapter and is held securely by the focuser's own locking collar or set screws, ensuring a rigid connection without the need for threads on the adapter itself.

    Is this Starlight Instruments adapter made of plastic or metal?

    This adapter is machined from high-quality aluminum. Starlight Instruments manufactures its components from metal to ensure maximum rigidity and durability, preventing any flexure in the optical train.

    Can I use this adapter to install a 3.5" Feather Touch on my Celestron SCT?

    No. This adapter is purpose-built for large TEC refractors and will not fit a Celestron Schmidt-Cassegrain Telescope (SCT). To mount a Feather Touch focuser on an SCT, you need a different adapter specifically designed for your SCT model's rear thread, such as the Starlight Instruments A20-292 or similar.

    Why should I choose a dedicated Starlight Instruments adapter for my TEC refractor?

    Using a dedicated adapter ensures a perfect mechanical fit with zero play or slop. This precision is critical in astrophotography, as any tilt or movement between the telescope and the focuser can lead to distorted stars and poor image quality. A genuine Starlight Instruments adapter guarantees the seamless integration and stability your high-end optics deserve.

  • Starlight Instruments 2-Year Warranty