PTEC-3600 to OPTEC-4300 Extension Ring (17870)

Regular price
$ 65.00
Sale price
$ 65.00
Unit price

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


The 3600 to 4300 Expansion Ring allows owners of any OPTEC-3600 telescope adapter to easily expand the male dovetail out to 4.3-inches matching the OPTEC-4300 spec.


Inside Diameter: 3.6" (91mm)
Outside Diameter: 4.95" (126mm)

Overall Height:

0.42" (10.7mm)
Clear Aperture: 3.6" (91mm)
Weight: 3.4 oz (100 g)
Back-Focus Usage: 0.1" (2.5mm)



  • Any OPTEC-3600 telescope adapter.
  • Gemini Focusing Rotator.
  • TCF-Lynx 3 3-inch Focuser.

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