Agena Synta / Vixen Style Dovetail Mounting Base / Shoe for Finders - M4 Screw for GSO Crayford Focuser

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In many telescope rack-and-pinion (R&P) focusers, the base for your finder bracket is molded onto the focuser body. When you replace your existing focuser with a Crayford focuser, you will lose this base to mount your finder. We sell an optional Synta/GSO-compatible dovetail base modified to fit GSO focusers so that you can attach your Synta/GSO-compatible finder brackets again. Thus, you will be able to mount your red dot, multi-reticle, or larger conventional finder on your telescope. Will work with most compatible bracket designs from Celestron, Orion, Synta, Vixen, etc.
This will work on most single or dual speed GSO refractor focusers. Installation on GSO Crayford focusers is very easy and one M4 screw is included to mount the base on the focuser. However, it will not work with William Optics focusers which use a larger M5 screw, or the GSO 112mm linear bearing focuser which does not have the 4mm set screw on the body. Also not meant for SCT telescopes which need a wider screw hole spacing.
Can also be used with many other telescope tubes. Drilled (but not threaded) to accommodate screws up to 4mm in diameter. Center-to-center screw hole spacing on your telescope must be 18.6mm (0.76") in order for this dovetail base to be compatible. Fits tubes 3.25" and larger in tube diameter (not telescope aperture), as well as flat surfaces.
Please see the photos above for detailed dimensions and to determine compatibility with your telescope or finder/finder bracket - we are unable to make specific recommendations about compatibility. Please also note that the hole spacing for the two additional screws along the optical axis (one of which is used for attaching this base to a focuser) is not fixed. Since only one screw hole is to be used at a time, this is not an issue.
The base is made of die-cast metal and features a large thumbscrew lock. Includes one (not two) M4 screw. Finish may be smooth black or hammertone gray, depending on available stock. Style of large silver locking thumbscrew may vary.
Additional Info
When ordering any Vixen style dovetail base (shoe), bar or plate, please note that there are two different size standards and applications in the industry. A Vixen/Synta dovetail base for this Agena product is smaller and generally has a slot opening to accommodate 32-34mm finder bracket dovetails. A Vixen base/clamp/saddle for mounts and telescopes is wider at 42-44mm. The two are not the same and are not interchangeable.
Please check the specifications of this item provided above to ensure that it will be compatible with your accessory before purchasing
Useful Resources
Click here for installation instructions and photos showing how this item can be utilized.
Other Information
- Country of Manufacture: China
In many telescope rack-and-pinion (R&P) focusers, the base for your finder bracket is molded onto the focuser body. When you replace your existing focuser with a Crayford focuser, you will lose this base to mount your finder. We sell an optional Synta/GSO-compatible dovetail base modified to fit GSO focusers so that you can attach your Synta/GSO-compatible finder brackets again. Thus, you will be able to mount your red dot, multi-reticle, or larger conventional finder on your telescope. Will work with most compatible bracket designs from Celestron, Orion, Synta, Vixen, etc.
This will work on most single or dual speed GSO refractor focusers. Installation on GSO Crayford focusers is very easy and one M4 screw is included to mount the base on the focuser. However, it will not work with William Optics focusers which use a larger M5 screw, or the GSO 112mm linear bearing focuser which does not have the 4mm set screw on the body. Also not meant for SCT telescopes which need a wider screw hole spacing.
Can also be used with many other telescope tubes. Drilled (but not threaded) to accommodate screws up to 4mm in diameter. Center-to-center screw hole spacing on your telescope must be 18.6mm (0.76") in order for this dovetail base to be compatible. Fits tubes 3.25" and larger in tube diameter (not telescope aperture), as well as flat surfaces.
Please see the photos above for detailed dimensions and to determine compatibility with your telescope or finder/finder bracket - we are unable to make specific recommendations about compatibility. Please also note that the hole spacing for the two additional screws along the optical axis (one of which is used for attaching this base to a focuser) is not fixed. Since only one screw hole is to be used at a time, this is not an issue.
The base is made of die-cast metal and features a large thumbscrew lock. Includes one (not two) M4 screw. Finish may be smooth black or hammertone gray, depending on available stock. Style of large silver locking thumbscrew may vary.
In many telescope rack-and-pinion (R&P) focusers, the base for your finder bracket is molded onto the focuser body. When you replace your existing focuser with a Crayford focuser, you will lose this base to mount your finder. We sell an optional Synta/GSO-compatible dovetail base modified to fit GSO focusers so that you can attach your Synta/GSO-compatible finder brackets again. Thus, you will be able to mount your red dot, multi-reticle, or larger conventional finder on your telescope. Will work with most compatible bracket designs from Celestron, Orion, Synta, Vixen, etc.
This will work on most single or dual speed GSO refractor focusers. Installation on GSO Crayford focusers is very easy and one M4 screw is included to mount the base on the focuser. However, it will not work with William Optics focusers which use a larger M5 screw, or the GSO 112mm linear bearing focuser which does not have the 4mm set screw on the body. Also not meant for SCT telescopes which need a wider screw hole spacing.
Can also be used with many other telescope tubes. Drilled (but not threaded) to accommodate screws up to 4mm in diameter. Center-to-center screw hole spacing on your telescope must be 18.6mm (0.76") in order for this dovetail base to be compatible. Fits tubes 3.25" and larger in tube diameter (not telescope aperture), as well as flat surfaces.
Please see the photos above for detailed dimensions and to determine compatibility with your telescope or finder/finder bracket - we are unable to make specific recommendations about compatibility. Please also note that the hole spacing for the two additional screws along the optical axis (one of which is used for attaching this base to a focuser) is not fixed. Since only one screw hole is to be used at a time, this is not an issue.
The base is made of die-cast metal and features a large thumbscrew lock. Includes one (not two) M4 screw. Finish may be smooth black or hammertone gray, depending on available stock. Style of large silver locking thumbscrew may vary.
Additional Info
When ordering any Vixen style dovetail base (shoe), bar or plate, please note that there are two different size standards and applications in the industry. A Vixen/Synta dovetail base for this Agena product is smaller and generally has a slot opening to accommodate 32-34mm finder bracket dovetails. A Vixen base/clamp/saddle for mounts and telescopes is wider at 42-44mm. The two are not the same and are not interchangeable.
Please check the specifications of this item provided above to ensure that it will be compatible with your accessory before purchasing
Useful Resources
Click here for installation instructions and photos showing how this item can be utilized.
Other Information
- Country of Manufacture: China

Agena Synta / Vixen Style Dovetail Mounting Base / Shoe for Finders - M4 Screw for GSO Crayford Focuser
