When we design our mirror mounts, we strive to make mounts that provide precision adjustments that really stay put. To give you the ultimate in precision, one of our design criteria is to approach the textbook definition of kinematic - where there exists precisely one constraint or actuator for each independent degree of freedom. That's why we use a cone-vee-flat configuration. To provide even more precision and durability, we use sapphire seats to ensure that repetitive adjustments do not leave tracks that would make positioning non-kinematic, and therefore non-deterministic and imprecise.
