Good used cavity optics still mounted in the frame of a SSY-1 Nd:YAG laser head. The optics are .50″(12.7mm) diameter x .187″(4.7mm) thick.
The output coupler is on the end of the frame with two mounting holes

Note: We will not export this laser rod. Export of this item is controlled by the U.S. Government and may require an export license.

More info on solid state lasers found HERE