The ZWO T2 1.25" Filter Adapter easily screws into the camera body on small ASI cameras with an internal T2 thread, allowing the use of standard 1.25" filters. Internal thread is M28.5 x 0.6. The adapter adds 1mm of optical thickness.
|Connection side A
||M42 x 0.75
|Connection side B||1.25", M28.5 x 0.6