Blue Fireball 2" to 1.25" Twist Lock Self Centering Eyepiece Adapter

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This popular eyepiece adapter allows 1.25" eyepieces and accessories to be used in 2" focusers, diagonals and barlows. Instead of a conventional locking thumbscrew that can push the eyepiece to one side, this innovative adapter uses a helical compression mechanism to not only grip the inserted eyepiece securely, but also center the eyepiece accurately within the adapter in the process. This mechanism is easily tightened or loosened by turning the large knurled twist lock ring at the top of the adapter.
The helical centering mechanism is controlled by an inner polypropylene compression ring (or collet) that will not mar your eyepieces. Its long length ensures that the adapter works well with smooth and recessed eyepiece barrels.
This practical and superb quality adapter is made from precision machined aluminum and is black anodized. The inside surface of this tube is black-matted to enhance contrast by reducing stray light reflections. It is also threaded to accept standard 2" telescope filters so you can use your 1.25" eyepieces with your 2" filters (be careful not to let the eyepiece barrel hit the filter though; To alleviate this problem, you can attach a 2" spacer ring (not included) to the Twist-Lock adapter to increase its overall length).
Specifications (Complete adapter):
- Total height = 1.20" (30.6mm)
- Weight = 2.8oz (79g)
- Compression band length = Approx. 16.5mm (0.65")
- Maximum diameter = 2.2" (55.8mm)
Specifications (2" lower spacer part only):
- Total height = 1.03" (26.1mm)
- Optical length = 0.08" (2.15mm)
- Clear aperture = 1.25" (31.7mm)
- Weight = 2oz (57g)
- Threads = M48x0.75 male and female
Manufacturer part number: E-11
Other Information
- Country of Manufacture: Taiwan
This popular eyepiece adapter allows 1.25" eyepieces and accessories to be used in 2" focusers, diagonals and barlows. Instead of a conventional locking thumbscrew that can push the eyepiece to one side, this innovative adapter uses a helical compression mechanism to not only grip the inserted eyepiece securely, but also center the eyepiece accurately within the adapter in the process. This mechanism is easily tightened or loosened by turning the large knurled twist lock ring at the top of the adapter.
The helical centering mechanism is controlled by an inner polypropylene compression ring (or collet) that will not mar your eyepieces. Its long length ensures that the adapter works well with smooth and recessed eyepiece barrels.
This practical and superb quality adapter is made from precision machined aluminum and is black anodized. The inside surface of this tube is black-matted to enhance contrast by reducing stray light reflections. It is also threaded to accept standard 2" telescope filters so you can use your 1.25" eyepieces with your 2" filters (be careful not to let the eyepiece barrel hit the filter though; To alleviate this problem, you can attach a 2" spacer ring (not included) to the Twist-Lock adapter to increase its overall length).
Specifications (Complete adapter):
- Total height = 1.20" (30.6mm)
- Weight = 2.8oz (79g)
- Compression band length = Approx. 16.5mm (0.65")
- Maximum diameter = 2.2" (55.8mm)
Specifications (2" lower spacer part only):
- Total height = 1.03" (26.1mm)
- Optical length = 0.08" (2.15mm)
- Clear aperture = 1.25" (31.7mm)
- Weight = 2oz (57g)
- Threads = M48x0.75 male and female
Manufacturer part number: E-11
This popular eyepiece adapter allows 1.25" eyepieces and accessories to be used in 2" focusers, diagonals and barlows. Instead of a conventional locking thumbscrew that can push the eyepiece to one side, this innovative adapter uses a helical compression mechanism to not only grip the inserted eyepiece securely, but also center the eyepiece accurately within the adapter in the process. This mechanism is easily tightened or loosened by turning the large knurled twist lock ring at the top of the adapter.
The helical centering mechanism is controlled by an inner polypropylene compression ring (or collet) that will not mar your eyepieces. Its long length ensures that the adapter works well with smooth and recessed eyepiece barrels.
This practical and superb quality adapter is made from precision machined aluminum and is black anodized. The inside surface of this tube is black-matted to enhance contrast by reducing stray light reflections. It is also threaded to accept standard 2" telescope filters so you can use your 1.25" eyepieces with your 2" filters (be careful not to let the eyepiece barrel hit the filter though; To alleviate this problem, you can attach a 2" spacer ring (not included) to the Twist-Lock adapter to increase its overall length).
Specifications (Complete adapter):
- Total height = 1.20" (30.6mm)
- Weight = 2.8oz (79g)
- Compression band length = Approx. 16.5mm (0.65")
- Maximum diameter = 2.2" (55.8mm)
Specifications (2" lower spacer part only):
- Total height = 1.03" (26.1mm)
- Optical length = 0.08" (2.15mm)
- Clear aperture = 1.25" (31.7mm)
- Weight = 2oz (57g)
- Threads = M48x0.75 male and female
Manufacturer part number: E-11
Other Information
- Country of Manufacture: Taiwan

Blue Fireball 2" to 1.25" Twist Lock Self Centering Eyepiece Adapter
