The Prototype Mirror Support System, designed by Eastman Kodak and Victor Krabbendam and built by George Barczak, ready for packing and shipping to Kodak for testing and evaluation. It is a modified Hindle mount, using three tetrahedrons made from 1/2-inch invar bar. Each of the 91 segments is mounted on an identical support. There is one actuator and a lever system for each tetrahedron. The three actuators on each support provide tip, tilt, and piston adjustment for each segment. There are 273 actuators for the entire 91-segment primary mirror.