#17829 - OPTEC-4300 Extension Ring, 12.5mm.
The OPTEC-4300 12.5mm Extension Ring provides approximately 1/2-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.
|Inside Diameter:||3.9" (99mm)|
|Outside Diameter:||4.95" (126mm)|
|Clear Aperture:||3.9" (99mm)|
|Weight:||5.0 oz (145 g)|
|Back-Focus Usage:||0.492" (12.5mm)|
- Any OPTEC-4300 telescope adapter.
- Gemini Focusing Rotator.
- TCF-Lynx3 3-inch Focuser.