#19839 - OPTEC-4300 Extension Adapter, 25mm length.


In Stock: 2

The OPTEC-4300 25mm Extension Ring provides approximately 1-inch of extension for any OPTEC-4300 telescope adapter. Ideal for telescopes where the Gemini Focusing Rotator may need to pushed out and away from the OTA to provide clearance for cooling fans or when a little extension is required to reach optimal focus.

  • Any OPTEC-4300 telescope adapter.
  • Gemini Focusing Rotator.
  • TCF-Lynx3 3-inch Focuser.
  • Inside Diameter: 3.9" (99mm)
  • Outside Diameter: 4.95" (126mm)
  • Overall Height: 1.30" (33.2mm)
  • Clear Aperture: 3.9" (99mm)
  • Weight: 8.8 oz (250 g)
  • Back-Focus Usage: 0.984" (25mm)