Blue Fireball Empty 1.25" Filter Cell with Retaining Ring

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- Buy 3 for $8.25 each and save 17%
Description/Uses:
- 1.25" empty filter cell for astronomy filters
- Great replacement for old, worn filter cells or those with threading issues
- Will accept filter substrates between 26.5mm and 27.7mm in diameter. Please measure your glass filter before purchasing this item to ensure fit.
- Can also be used as a 1.25" 7.7mm long spacer ring
Features:
- Precision machined from aluminum and black anodized
- Has standard 1.25" filter threads (male on one side and female on the other)
- Threads into any standard 1.25" eyepiece, barlow, diagonal, camera nosepiece, and accessories with compatible female thread
- Includes retaining ring with two notches 180-degrees apart to hold glass filter substrate within filter cell
- Made in Taiwan
Specifications:
- Total length of filter cell = 0.44" (11.2mm)
- Extension provided = 0.30" (7.7mm)
- Length of external male thread = 0.14" (3.5mm) including unthreaded undercut; 0.1" (2.5mm) excluding undercut
- Thread specification (external thread) = M28.5x0.6 male
- Length of internal female thread = 0.24" (6.1mm)
- Thread specification (internal thread) = M28.5x0.6 female
- Maximum outside diameter = 1.23" (31.3mm)
- Retaining ring length = 0.1" (2.5mm)
- Will accept unmounted filters between 26.5mm and 27.7mm in diameter and up to 3.5mm thick
Other Information
- Country of Manufacture: Taiwan
Description/Uses:
- 1.25" empty filter cell for astronomy filters
- Great replacement for old, worn filter cells or those with threading issues
- Will accept filter substrates between 26.5mm and 27.7mm in diameter. Please measure your glass filter before purchasing this item to ensure fit.
- Can also be used as a 1.25" 7.7mm long spacer ring
Features:
- Precision machined from aluminum and black anodized
- Has standard 1.25" filter threads (male on one side and female on the other)
- Threads into any standard 1.25" eyepiece, barlow, diagonal, camera nosepiece, and accessories with compatible female thread
- Includes retaining ring with two notches 180-degrees apart to hold glass filter substrate within filter cell
- Made in Taiwan
Specifications:
- Total length of filter cell = 0.44" (11.2mm)
- Extension provided = 0.30" (7.7mm)
- Length of external male thread = 0.14" (3.5mm) including unthreaded undercut; 0.1" (2.5mm) excluding undercut
- Thread specification (external thread) = M28.5x0.6 male
- Length of internal female thread = 0.24" (6.1mm)
- Thread specification (internal thread) = M28.5x0.6 female
- Maximum outside diameter = 1.23" (31.3mm)
- Retaining ring length = 0.1" (2.5mm)
- Will accept unmounted filters between 26.5mm and 27.7mm in diameter and up to 3.5mm thick
Description/Uses:
- 1.25" empty filter cell for astronomy filters
- Great replacement for old, worn filter cells or those with threading issues
- Will accept filter substrates between 26.5mm and 27.7mm in diameter. Please measure your glass filter before purchasing this item to ensure fit.
- Can also be used as a 1.25" 7.7mm long spacer ring
Features:
- Precision machined from aluminum and black anodized
- Has standard 1.25" filter threads (male on one side and female on the other)
- Threads into any standard 1.25" eyepiece, barlow, diagonal, camera nosepiece, and accessories with compatible female thread
- Includes retaining ring with two notches 180-degrees apart to hold glass filter substrate within filter cell
- Made in Taiwan
Specifications:
- Total length of filter cell = 0.44" (11.2mm)
- Extension provided = 0.30" (7.7mm)
- Length of external male thread = 0.14" (3.5mm) including unthreaded undercut; 0.1" (2.5mm) excluding undercut
- Thread specification (external thread) = M28.5x0.6 male
- Length of internal female thread = 0.24" (6.1mm)
- Thread specification (internal thread) = M28.5x0.6 female
- Maximum outside diameter = 1.23" (31.3mm)
- Retaining ring length = 0.1" (2.5mm)
- Will accept unmounted filters between 26.5mm and 27.7mm in diameter and up to 3.5mm thick
Other Information
- Country of Manufacture: Taiwan

Blue Fireball Empty 1.25" Filter Cell with Retaining Ring
