The ZWO M68 Off-Axis Guider helps you guide your astrophotography rig while imaging without the use of a guide scope. This helps avoid flexure issues that can arise, especially when using long focal length scopes (ask us about our experiences here!).
It can be used as an M54 to M48 adapter for the M54 cameras, such as the ASI6200.
Flexure occurs when various factors such as the movement of the equipment causes tiny variable differences in the direction that a guide scope is pointing vs where the imaging scope is pointing, causing distortions in tracking and less than perfect images.
The OAG allows a guide camera to use the imaging scope as the guide scope, eliminating sources of flexure introduced by guide scopes. The pick-off prism allows the guide camera to use a star near the edge of the image for guiding purposes, while staying far enough out of the light circle as to not cause a shadow on the main imaging sensor.
The pick-off prism position is adjustable, allowing you to rotate the OAG and move it inwards and outwards in order to identify a good guide star near the edge of the view that helps avoid adjusting the main scope pointing to find a guide star.
Please review this link for connection methods for the ASI6200MM Pro, 2" EFW and M68 OAG: