Put this on the Optics forum but have since learned that it is probablyfor an airgun. Can anyone give me info on it?

This came to me in a box of rings and parts. Can anyone tell me what they are for? There were two rails in there that looked as though they were intended to be used for mounting it, but they are too wide.

An older RWS airgun mount.Have one on my 80's San Rafael Beeman R1.