Nickle finish aluminum housing measures 15 inches across in diameter. Depth is about 1/2" except where porthole clamps are at 3" tall. Weight approximately 4 lbs.
Glass Mirror portion is 10.5" across in diameter. When porthole is opened, there is a circular space of approximately 12" across in diameter.
Three countersunk screw holes for mounting (under clamps and hinge areas so hidden from view). Brand new and packaged very well for transit.