Blue Fireball SCT Thread Spacer Ring with 1" Extension (Short Thread Version) # S-SB

Our Price: $20.95

Sale Price: $14.67

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In Stock (10+ Available)
Ships by Next Business Day
Our Product ID: PAAR-BF-S-SB
Manufacturer SKU: S-SB
Item Can Ship: Worldwide
Blue Fireball SCT Thread Spacer Ring with 1" Extension (Short Thread Version) # S-SB

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Please Note: Please read the item specifications below very carefully before purchasing this item. Note that the the female SCT thread on this item is rather short. This item will not work if you try to connect it to the SCT male thread on SCT telescopes or SCT focal reducers (since these have a tapered, unthreaded tip and this adapter is unable to engage, or unable to engage sufficiently, with the recessed threads). This item will work well if connected to SCT accessories in which the male SCT thread is machined all the way to the end, but is not recommended for direct attachment to SCT telescopes, diagonals, or focal reducers.

For use with SCT reducers and diagonals, please see Blue Fireball item # S-SE instead.


  • SCT thread extension ring/barrel spacer
  • Provides 1" (25.4mm) of spacing
  • Allows you to securely set or vary the spacing between SCT thread components
  • Has standard SCT threads (male on one side and female on the other)


  • Precision machined from aluminum and black anodized


  • Total Length = 1.16" (29.4mm)
  • Extension Provided = 1" (25.4mm)
  • Length of External Male Thread = 0.16" (4mm)
  • Thread Specification (External Thread) = 2"x24TPI Male
  • Length of Internal Female Thread = 0.17" (4.2mm)
  • Thread Specification (Internal Thread) = 2"x24TPI Female
  • Maximum Outer Diameter = 2.17" (55mm)
  • Weight = 1.4oz (40g)

Additional Information:
* To get a spacing of 1" (25.4mm) with this spacer, your accessory must fit completely into the female SCT thread of this adapter. The length of the female SCT thread is 0.17" (4.2mm). If your accessory has a male SCT thread longer than this, then it will not screw in fully and the extension provided will be greater than 1".