Bob's Knobs iOptron 6'' RC Secondary Collimation Knobs

Bob's Knobs iOptron 6" RC Secondary Collimation Knobs

  (2 Reviews)
✓ 2 year warranty


1x in stock shipped 1-2 working days

About this product

Model:  bk_at6rc_sec
Part Number:  AT6RC

Replacement collimation knobs for iOptron / Astro-Tech / GSO / Orion / TPO 6" RC Series telescopes.

Bob's Knobs are the BEST option for tool-free collimation.

Simple to fit and easy to use.

Collimate your telescope without an Allen key or screwdriver!

Instructions are supplied but can also be found online as well as useful FAQ.

Images are representative and may not show the exact knob size / threads.

IMPORTANT: Please ensure the Bob's knobs threads and factory screw threads match before installation.

Knobs for iOptron / Astro-Tech / GSO / Orion / TPO 6" f/9 Ritchey-Crétien Secondary

Part: AT6RC
Fits: Astro-Tech, GPO, Orion (US), and TPO 6" f/9 RCT secondary (solid or truss-tube)

Knobs: Black plastic, 16 mm (5/8”) diameter
Threads: Stainless Steel.

Customer reviews

Average Rating (2 Reviews):  
Write a Review and share your opinions!

Rating (max 5):  
26 August 2022  | 

I bought these for my Stellalyra RC6 and with a screw length of 22mm they work perfectly. Dust cap fits too. Makes secondary mirror collimation a lot easier than Allen keys. Rapid and well packaged service from FLO as usual.

Rating (max 5):  
Bob's Knobs for 6 inch RC (StellaLyra)
08 October 2020  | 

The set were well made can't fault them on that, they were however too short so I ended up returning them for a refund. Hense the 3 stars.


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