GSO Primary Mirror Cell for 12" Mirrors (with Cooling Fan)

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- GSO Mirror Cell for telescope mirrors with diameter of 304mm (11.97")
- Provides excellent support and protection of telescope mirror
- Fits mirrors with thickness 32mm to 38mm
- Includes three collimation and three locking knobs and nine flotation points
- Comes with DC cooling fan (power supply not included)
The GSO 12" Mirror Cell is an affordable but full-featured primary mirror holder for reflecting telescopes. Made from CNC-machined metal, this cell is designed to make it easy to securely mount your telescope mirror to a telescope tube and collimate it to the optical axis of the telescope. It's the same mirror cell used in many GSO telescopes.
This cell works with mirrors with a maximum diameter of 304mm (11.97").
Three adjustable tabs allow you to securely mount mirrors from 32mm to 38mm in thickness. The GSO mirror cell incorporates 9 flotation points to support the mirror and protect it from shocks while you're transporting and setting up your telescope. Three push-pull knobs and three locking knobs let you easily collimate your telescope and lock the angular position of the mirror to maintain collimation during observing sessions and transport.
The mirror cell also includes a cooling fan to help bring the mirror to thermal equilibrium quickly. The fan requires 12V DC (max) from a source with a 2.1mm tip (power supply not included). Or you can use 4xAA batteries in a compact GSO battery holder (sold separately).
Telescope tubes with an inside diameter (ID) smaller than 355mm will not mount to this mirror cell. Tubes with an ID slightly larger than 355mm may require the addition of shims to hold the cell against the tube. Telescope tubes with an outside diameter (OD) between 355mm and 360mm will fit into the tube slot of the mirror cell. If your tube OD is slightly larger than 360mm, it can still be used with this cell but the tube will not seat inside the tube slot on the cell. The GSO mirror cell includes six threaded M4 holes for mounting to the telescope tube. M4 mounting screws are not included.
The mirror cell weighs 4lbs 8oz.
Specifications:
- Mirror Related Specifications
- Maximum mirror diameter: 304mm (11.97"). Please note that this is a little smaller than 12".
- Minimum mirror thickness: 32mm (1.26")
- Maximum mirror thickness: 38mm (1.46")
- Collimation knobs: 3 axial push-pull knobs (black) and 3 locking knobs (white)
- Axial fixed support: 9 axial rubber pads on 3 swivel mounts
- Radial fixed support: None - mirror touches fall prevention support
- Flotation points: 9
- Tube Related Specifications
- Minimum telescope tube inside diameter (ID): 355mm (13.98"). Tubes with an ID smaller than this will not be able to accept this mirror cell. Tubes with an ID slightly larger than this will require you to add shims to hold the mirror cell.
- Maximum telescope tube inside diameter (OD): 360mm (14.17"). Tubes between 355mm ID and 360mm OD will fit into the tube slot of the mirror cell and the cell will be at the rear of the tube as you will see on most conventional telescopes. If your tube OD is slightly larger than 360mm, it can still be used but the tube will not seat inside the tube slot on the mirror cell.
- Tube attachment: Six M4 threaded holes on rim of mirror cell (screws not included)
- Mirror Cell Specifications
- Cell weight: 4lbs-8oz
- Total cell length/height: 76mm (3")
- Maximum cell outside diameter: 363mm (14.29")
- Cooling fan: Yes - requires 12V DC (max) power supply with 2.1mm tip. Power supply not included. 6V battery pack holder sold separately.
- Fall prevention: 3 supports (holding mirror from top and side); can be adjusted (increased) for mirror thickness up to 5mm from minimum position using included M5x35mm screws (6x)
- Made in Taiwan
Other Information
- Country of Manufacture: Taiwan
The GSO 12" Mirror Cell is an affordable but full-featured primary mirror holder for reflecting telescopes. Made from CNC-machined metal, this cell is designed to make it easy to securely mount your telescope mirror to a telescope tube and collimate it to the optical axis of the telescope. It's the same mirror cell used in many GSO telescopes.
This cell works with mirrors with a maximum diameter of 304mm (11.97").
Three adjustable tabs allow you to securely mount mirrors from 32mm to 38mm in thickness. The GSO mirror cell incorporates 9 flotation points to support the mirror and protect it from shocks while you're transporting and setting up your telescope. Three push-pull knobs and three locking knobs let you easily collimate your telescope and lock the angular position of the mirror to maintain collimation during observing sessions and transport.
The mirror cell also includes a cooling fan to help bring the mirror to thermal equilibrium quickly. The fan requires 12V DC (max) from a source with a 2.1mm tip (power supply not included). Or you can use 4xAA batteries in a compact GSO battery holder (sold separately).
Telescope tubes with an inside diameter (ID) smaller than 355mm will not mount to this mirror cell. Tubes with an ID slightly larger than 355mm may require the addition of shims to hold the cell against the tube. Telescope tubes with an outside diameter (OD) between 355mm and 360mm will fit into the tube slot of the mirror cell. If your tube OD is slightly larger than 360mm, it can still be used with this cell but the tube will not seat inside the tube slot on the cell. The GSO mirror cell includes six threaded M4 holes for mounting to the telescope tube. M4 mounting screws are not included.
The mirror cell weighs 4lbs 8oz.
Specifications:
- Mirror Related Specifications
- Maximum mirror diameter: 304mm (11.97"). Please note that this is a little smaller than 12".
- Minimum mirror thickness: 32mm (1.26")
- Maximum mirror thickness: 38mm (1.46")
- Collimation knobs: 3 axial push-pull knobs (black) and 3 locking knobs (white)
- Axial fixed support: 9 axial rubber pads on 3 swivel mounts
- Radial fixed support: None - mirror touches fall prevention support
- Flotation points: 9
- Tube Related Specifications
- Minimum telescope tube inside diameter (ID): 355mm (13.98"). Tubes with an ID smaller than this will not be able to accept this mirror cell. Tubes with an ID slightly larger than this will require you to add shims to hold the mirror cell.
- Maximum telescope tube inside diameter (OD): 360mm (14.17"). Tubes between 355mm ID and 360mm OD will fit into the tube slot of the mirror cell and the cell will be at the rear of the tube as you will see on most conventional telescopes. If your tube OD is slightly larger than 360mm, it can still be used but the tube will not seat inside the tube slot on the mirror cell.
- Tube attachment: Six M4 threaded holes on rim of mirror cell (screws not included)
- Mirror Cell Specifications
- Cell weight: 4lbs-8oz
- Total cell length/height: 76mm (3")
- Maximum cell outside diameter: 363mm (14.29")
- Cooling fan: Yes - requires 12V DC (max) power supply with 2.1mm tip. Power supply not included. 6V battery pack holder sold separately.
- Fall prevention: 3 supports (holding mirror from top and side); can be adjusted (increased) for mirror thickness up to 5mm from minimum position using included M5x35mm screws (6x)
- Made in Taiwan
- GSO Mirror Cell for telescope mirrors with diameter of 304mm (11.97")
- Provides excellent support and protection of telescope mirror
- Fits mirrors with thickness 32mm to 38mm
- Includes three collimation and three locking knobs and nine flotation points
- Comes with DC cooling fan (power supply not included)
The GSO 12" Mirror Cell is an affordable but full-featured primary mirror holder for reflecting telescopes. Made from CNC-machined metal, this cell is designed to make it easy to securely mount your telescope mirror to a telescope tube and collimate it to the optical axis of the telescope. It's the same mirror cell used in many GSO telescopes.
This cell works with mirrors with a maximum diameter of 304mm (11.97").
Three adjustable tabs allow you to securely mount mirrors from 32mm to 38mm in thickness. The GSO mirror cell incorporates 9 flotation points to support the mirror and protect it from shocks while you're transporting and setting up your telescope. Three push-pull knobs and three locking knobs let you easily collimate your telescope and lock the angular position of the mirror to maintain collimation during observing sessions and transport.
The mirror cell also includes a cooling fan to help bring the mirror to thermal equilibrium quickly. The fan requires 12V DC (max) from a source with a 2.1mm tip (power supply not included). Or you can use 4xAA batteries in a compact GSO battery holder (sold separately).
Telescope tubes with an inside diameter (ID) smaller than 355mm will not mount to this mirror cell. Tubes with an ID slightly larger than 355mm may require the addition of shims to hold the cell against the tube. Telescope tubes with an outside diameter (OD) between 355mm and 360mm will fit into the tube slot of the mirror cell. If your tube OD is slightly larger than 360mm, it can still be used with this cell but the tube will not seat inside the tube slot on the cell. The GSO mirror cell includes six threaded M4 holes for mounting to the telescope tube. M4 mounting screws are not included.
The mirror cell weighs 4lbs 8oz.
Specifications:
- Mirror Related Specifications
- Maximum mirror diameter: 304mm (11.97"). Please note that this is a little smaller than 12".
- Minimum mirror thickness: 32mm (1.26")
- Maximum mirror thickness: 38mm (1.46")
- Collimation knobs: 3 axial push-pull knobs (black) and 3 locking knobs (white)
- Axial fixed support: 9 axial rubber pads on 3 swivel mounts
- Radial fixed support: None - mirror touches fall prevention support
- Flotation points: 9
- Tube Related Specifications
- Minimum telescope tube inside diameter (ID): 355mm (13.98"). Tubes with an ID smaller than this will not be able to accept this mirror cell. Tubes with an ID slightly larger than this will require you to add shims to hold the mirror cell.
- Maximum telescope tube inside diameter (OD): 360mm (14.17"). Tubes between 355mm ID and 360mm OD will fit into the tube slot of the mirror cell and the cell will be at the rear of the tube as you will see on most conventional telescopes. If your tube OD is slightly larger than 360mm, it can still be used but the tube will not seat inside the tube slot on the mirror cell.
- Tube attachment: Six M4 threaded holes on rim of mirror cell (screws not included)
- Mirror Cell Specifications
- Cell weight: 4lbs-8oz
- Total cell length/height: 76mm (3")
- Maximum cell outside diameter: 363mm (14.29")
- Cooling fan: Yes - requires 12V DC (max) power supply with 2.1mm tip. Power supply not included. 6V battery pack holder sold separately.
- Fall prevention: 3 supports (holding mirror from top and side); can be adjusted (increased) for mirror thickness up to 5mm from minimum position using included M5x35mm screws (6x)
- Made in Taiwan
Other Information
- Country of Manufacture: Taiwan

GSO Primary Mirror Cell for 12" Mirrors (with Cooling Fan)
