6" mirror, approximately f/2 (~24" radius), appears spherical, and appears smooth with a knife edge
but I do not have any good testing facility. Also, appears to be pyrex, but I cannot guarantee this other
than this is not plate glass.
Based on where the mirror came from, it is likely a lab surplus or military/research surplus, but again
I cannot guarantee this.
Selling for $125 which includes shipping in the USA. Reasonable offers will be considered. Coatings are in good
condition, no sleeks or chips on the surface, one very small chip on the back edge. Selling this item "as is" because
I cannot test it.