The T2 adapter connects T2 lenses, which themselves have a standardised T2 connection thread, to your camera and its bayonet connection. It is screwed onto the lens and the lens can then be attached.
Important: The T2 adapter is a purely mechanical connection or transition ring, it does not use any control contacts, AF drives or aperture control contacts of your camera.
In most cases, lenses with a T2 connection can be used on your camera with the aperture priority, but certainly with the manual setting of time and aperture.