Skip to content
Until May 2nd, 2025, orders under US$800 will not incur any duties or taxes upon delivery. Please note that orders under US$800 crossing the Canada-USA border after this date will be subject to duties. They will be billed by the carrier, and you will be responsible to pay them. Prioritize ordering items that are in stock!
Until May 2nd, 2025, orders under US$800 will not incur any duties or taxes upon delivery. Please note that orders under US$800 crossing the Canada-USA border after this date will be subject to duties. They will be billed by the carrier, and you will be responsible to pay them. Prioritize ordering items that are in stock!

Part:CNsec30 or CNsec35
Fits: Celestron C6-N/NGT, C8-N/NGT, and C10-N/NGT Newtonian telescopes, SkyWatcher (5”, 6”, 8”, 10”, 12”, 14”, 16”) Newtonian telescopes.

Knobs: Black plastic, 13 mm (1/2”) diameter
Threads: Stainless steel

We offer knobs with screws having either 30 mm or 35 mm length. Order knobs with a screw length sufficient to allow the knobs to clear the secondary housing. Knobs with 30 mm screws are the most common in this configuration.

You may also like

  • $28.00 USD - $28.00 USD
    $28.00 USD
    $28.00 USD - $28.00 USD
    $28.00 USD

    Bob's Knobs for C6 SCT - Stainless Steel

    BOB-C6SS

    The collimation of an SCT can be a daunting task for a beginner, but it is an absolutely necessary process to get the most out of your telescope! D...

    View full details
    $28.00 USD - $28.00 USD
    $28.00 USD
    $28.00 USD - $28.00 USD
    $28.00 USD
  • $28.00 USD - $28.00 USD
    $28.00 USD
    $28.00 USD - $28.00 USD
    $28.00 USD

    Bob's Knobs for C5 SCT Metric - Stainless Steel

    BOB-C5metSS

    The collimation of an SCT can be a daunting task for a beginner, but it is an absolutely necessary process to get the most out of your telescope! D...

    View full details
    $28.00 USD - $28.00 USD
    $28.00 USD
    $28.00 USD - $28.00 USD
    $28.00 USD
  • $28.00 USD - $28.00 USD
    $28.00 USD
    $28.00 USD - $28.00 USD
    $28.00 USD

    Bob's Knobs for C8 SCT - Stainless Steel

    BOB-C8metSS

    Fits: Most Celestron 8” (20 cm) f/10 SCT made in 2005 and later with black Phillips factory collimation screws that have metric threads. Includes S...

    View full details
    $28.00 USD - $28.00 USD
    $28.00 USD
    $28.00 USD - $28.00 USD
    $28.00 USD
  • $28.00 USD - $28.00 USD
    $28.00 USD
    $28.00 USD - $28.00 USD
    $28.00 USD

    Bob's Knobs for SkyWatcher Newtonian Primary with Factory Collimation Screws

    BOB-SWpri

    Primary collimation Knobs: Black plastic, 16 mm (5/8”) diameter Threads: Stainless steel Primary Lock Knobs: Red plastic, 16 mm (5/8”) diamete...

    View full details
    $28.00 USD - $28.00 USD
    $28.00 USD
    $28.00 USD - $28.00 USD
    $28.00 USD
  • $25.00 USD - $25.00 USD
    $25.00 USD
    $25.00 USD - $25.00 USD
    $25.00 USD

    Bob's Knobs Collimation Thumbscrews for C9.25 Fastar - Stainless Steel

    BOB-C9.25fst
    3 in stock

    The collimation of an SCT can be a daunting task for a beginner, but it is an absolutely necessary process to get the most out of your telescope! D...

    View full details
    $25.00 USD - $25.00 USD
    $25.00 USD
    $25.00 USD - $25.00 USD
    $25.00 USD