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2-inch to 1-1/4-inch Precision Centering Standard Adapter (17662)

  • 4500

This item is out of stock but you can place an order now and we’ll ship when it becomes available.


Adapters for 2-inch Focuser Drawtubes

2-inch O.D. Adapters to fit the TCF-S and other 2-inch focusers.

Each of our 2-inch Drawtube adapters are machined to tight tolerances for a smooth, snug fit into the TCF-S and TCF-Si 2-inch focuser drawtubes. A dovetail cut directly matches the thumbscrews on the TCF-S for a secure fit.  By tightening the thumbscrews, the adapter is drawn tightly into the focuser's drawtube.

These 2-inch drawtube adapters will usually fit very well into other manufacturer's focusers as well.   Contact Optec for any 2-inch drawtube adapter not listed here.

#17662 - 2-inch to 1-1/4-inch Precision Centering Standard Adapter

The  2-inch to 1-1/4-inch Standard Adapter is our original secure fit adapter for 1-1/4-inch eyepieces, camera nosepieces, and SSP instrument telescope adapters.

See our #17663 Precision Centering Adapter for a non-marring compression ring fitting for eyepieces and camera nosepieces.  However, for those desiring the additional safely of a dovetail groove, the #17662 is a better choice. 

With a heavy wall and single thumbscrew lock, the #17662 is both rugged and easy to use.  The bottom side flange features a machined brass registration screw to exactly match the notch on all TCF-S focusers.  This allows rotational alignment each time the #17662 is removed and re-inserted into the 2-inch drawtube.


  • Overall Outside Diameter:  2.38" (60mm)
  • Outside Diameter (main body):  1.995" (50.7mm)
  • Overall Height: 1.40" (35.5mm)
  • Clear Aperture: 1.25" (31.8mm)
  • Weight: 4.6 oz (135 g)
  • Back-focus Usage: 0.25" (6.4 mm)

Compatible with:

  • TCF-S or TCF-Si focuser,
  • TCF-S3 or TCF-S3i focuser with #17804 3-inch to 2-inch reducer,
  • Any manufacturer's 2-inch focuser or receiver.

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