A metal T2 adapter that allows you to attach a Micro Four Thirds / m43 camera to a telescope or astronomical telescope with a T2 mount, for example.

T2 adapter that allows you to attach OM System / Panasonic Micro Four Thirds M43 mount mirrorless cameras to any T2 (T-Mount) mount.
Most commonly, this is used to attach a camera to a telescope or astronomical telescope, allowing the telescope to truly act as a telephoto lens.
The T2 adapter is screwed onto the T2 thread of the optic/accessory. The camera body is attached to the other end of the adapter.
Camera mount: MFT / m43
Lens mount: T2